Gunsmiths, gun collectors, gun-oriented internet forums, you might find someone at the gun show who'll know something about it.
Try local gun shops, the yellow and white pages.
Try gun shops, gun shows, want ads, Sears memoribilia collectors.
As of 2012, there were 51,438 retail gun stores, and 7,356 pawn shops with a gun dealer's license. There are about 62,000 collectors with a Federal Firearms license.
Blue Book of Gun Values, The Parker Gun Collectors Association
look on the net for a marlin gun collectors site, they have that info.
Dealers and collectors. Start with the yellow pages under gun shops.
CHECK THE WINCHESTER GUN COLLECTORS SITE
collections
colt gun collectors site has the info, google it
There are several surviving examples, typically in museums or in the hands of licenced collectors.
wells