I wondered if that was the one when I saw your post. There are other pistols scattered around at various historic sites in Nebraska, but that is one of the few flintlocks.
You were about 130 miles SSE of the site of this year's "gathering of gunstockers", an informal sorta-annual get-together of about a dozen riflemakers and almost as many collectors. We aren't particularly well-organized, but it is a great way to see and handle originals, and talk rifle-building. I don't recall exact numbers, but I know there were flint pistols there from Wheeler, Deringer, Chance, and Ketland that weekend.