A number of books on cowboy and western collectibles have been written. I only featured essential items in my Trigger book. Roy Rogers made more money through merchandising and personal appearances than from movies and television shows. He had the good fortune and enough business savvy to own his screen name and likeness. 

Roy Rogers and Trigger Lucky Horseshoe Game
Set; Ohio Art Tin Litho; 1950.
Trigger Rollfast bike, 1952.
Roy Rogers Comics #5; 1948 featuring Little Trigger and Harvester-Trigger. 
Trigger button and marble, small but often expensive even in today’s waning market.
Trigger button.
Roy Rogers’ Trigger (Four Color 329) comic book, the first issue produced in 1951; oil painting possibly by Morris Gollub.
Mini-Roy Rogers and Trigger Hartland figures, mint on card. Note the price!
Roy Rogers dinner plate.
Post Grap-Nuts pop out cards, 36 colorful items in all.
Horse shoe worn by Trigger mounted on a wood plaque, 1964.
Roy Rogers and Trigger cookie jar produced in 1995; 17.5 inches high (Roy Dillow Collection).
Breyer Roy Rogers Trigger posable plush toy. Note the single rear white stocking, something toy creators later paid detailed attention to.  Even the 45-degree angle in the blaze as it hits the nostrils is correct.
Roy Rogers and Trigger bobber. 
Roy Rogers and Trigger comic #100 and the Roy Rogers tablet, featuring three 
spot illustrations by Sam Savitt. That’s Little Trigger in the photo. 
Trigger resin sculpture by Brigitte Eberl. As far as I know, this was a one 
of-a-kind commissioned piece. Striking!
Trigger and Buttermilk painting sold by Burley Auctions.
Roy Rogers and Trigger porcelain sculpture limited edition on a hardwood base with name plaque, 2006 (Roy Dillow Collection).
Back cover of the Roy Rogers and Dale Evans Cut Out Book; Whitman Publishing; 1950.
Larry “Rocky” Roe’s wonderful customized Trigger with accurate markings from a Breyer rearing stallion.
My Pal Trigger lobby card, one of about a half-dozen depicting key movie scenes (Roy Dillow Collection).
Life magazine: Roy Rogers and Little Trigger on the cover dated July 12, 1943. Volume 15, Number 2. The sad irony, Simi Valley in the background became the porn capital of the country.
The Olaf Weighorst oil portrait of Trigger (Little Trigger more likely) that hung in the Rogers study and sold for $25,000 at auction in Mesa, Arizona, in 2002. 
Roy Rogers and Dale Evans lunch box with Trigger front and center (Roy Dillow Collection).
Roy Rogers and Trigger Hobby-Art plaque sets.
Roy Rogers Stillmeadow porcelain cup.
Trigger pocket knife. Champion and Silver were also featured on knives.
Trigger pull toy; NN Hill Brass company.
Trigger plush with hat.
Trigger western tie.
Trigger vintage bowl. There are a number of items in the set including a matching cup. 
Beswick #1374 galloping palomino modeled after Roy Rogers’ Trigger, though I’m not sure it was ever marketed as such (Roy Dillow Collection).
Rare Trigger ceramic mug.
Personally customized Trigger commissioned for the Roy Dillow collection.
Roy Rogers Apple Valley Inn postcard featuring Dale Evans and Little Trigger.
Beswick high-quality porcelain Roy Rogers and Trigger model. The British company is best known for its highly collectible Beatrix Potter characters (Roy Dillow Collection).
Roy Rogers and rearing Trigger Hartland figures; walking and semi-rearing Triggers were also produced and sold primarily through Sears.
Although not produced as Trigger, a gem like this golden horse clock would be treasured by Roy Rogers collectors. 
Spanish Trigger comic, cover by Sam Savitt. “Tigre” literally translates to “tiger.” 
Roy Rogers Marx trailer hauler which comes with a number of rubber figures.
Trigger Breyer figure with VHS of The Golden Stallion. Again notice the rear white sock (Roy Dillow Collection).
Roy Rogers collectors gravitate toward golden metal western statues although they are not produced as Trigger in particular, only those made by Estes Tarter were.
Roy Rogers Comics #86 (1945) featuring one of the earliest photographs of Little Trigger. 
Custom painted Dale Evans and Roy Rogers Hartlands from the fabulous Roy Dillow collection. 
Trigger metal pin-back. I believe a Post Cereal box prize
Heavy metal statue with base and plaque. The four white stocking are more Trigger Jr than the original horse (Roy Dillow collection).
Rafael DeSoto oil back cover for Roy Rogers’ Trigger (Four-Color Comics #329) produced in 1951 for Dell.  
Dale Evans and Buttermilk Hartland figures.
Post Grape Nuts Trigger metal ring.
Yet another customized Roy Rogers and semi-rearing Trigger Hartland set from Roy Dillow’s never ending collection.
Australian comics 19 and 9, early 1950s.
Of the different Hartland horses, the Custer palomino resembles Trigger closest. This pair from the Roy Dillow collection work well together. All that’s missing is the painted breast plate. Too bad the duo was never offered as an alternative.
The Golden Stallion poster, Republic Pictures. Six Roy Rogers movies were built around Trigger.
Trigger porcelain sculpture figure offered by the Roy Rogers Museum in Victorville (Roy Dillow Collection).
Street signs denoting Trigger Street and Trigger Place may be found in San Fernando Valley, Chatsworth, California. Photo by Alana Coghlan.
Custom Roy Rogers and semi-rearing Trigger Hartlands from the Roy Dillow collection.
Many versions of the great Marx set were produced. The horses varied from cream to golden colored; from semi-rearing to running. After an unresolved legal dispute, the set was released as plain cowboy and horse
Coin Operated Trigger.
Roy Rogers Trigger Inflatable