Flintsteel: that is truly a beautifully made rifle and you are lucky to be the current curator. It is my observation that there will always be a market for that kind of workmanship. But you are unlikely to find a buyer at a flea market. Most folks, as you have said, are tire kickers, and want you to lower your price. The issue then isn't whether a buyer at the high end exists,...it's finding them! There are many scratch builders on this site that regularly sell their best quality work for what it is worth. These same builders can take a "kit gun" and turn it into something that resembles your Armstrong (Kirkland) rifle. I myself confess to doing that when a client wants a nice carved, engraved, and inlaid rifle for less than a scratch built rifle costs. This creates two happy people, ie: I the builder and he (she) the client. I now build only for myself, and though I have a fairly long list of builds that I intend to complete before I 'go to my reward', I also intend to build Kibler's Classsic Longrifle. I'm looking forward to it too.
My children and good wife should she outlive me, will have to deal with my collection though...I'm not in a hurry to part with anything in my stable...for any money.