As stated above, buy the gun, not the story.

The only way I might even consider such a gun is if there was solid proof that a firearm with a certain serial number was linked to a reknowned individual. Such as if a factory letter from Roy Jinks stated that it was shipped to Pancho Villa. Other documentation that might be acceptable would be official documentation originating from an authority such as a confiscating official or maybe a documentation of the estate of an individual documented by an authority or public official. Such as a will or documentation of the property in a public record made at a time contemporary to the individual, and not altered or forged.

A letter from a saddle maker from 1936--I could create a few hundred of these in an afternoon.

I once was offered for sale at a tag sale in the late 1990's Robert E Lee's coffee grinder. Had a patent date of around 1900 on it and Lee died in 1870. But the fellow selling it insisted that his grandfather or great grandfather bought it off of the estate of Robert E Lee. Now, if he said so, it certainly must be so!