Guys, I hate to be the sour grape here, but I'm flying the BS flag on this one.
And to be clear: the story could be true. We have no evidence to suggest that it couldn't be true, given that the gun was shipped to Storrs, and from there could have gone anywhere (as virtually all of these guns did).
But it really seems to hinge on this affidavit, which is really just a fancy name for written-down family folklore. Being notarized and written in legalese doesn't make it any more true. That there is nobody around to dispute it similarly doesn't make it true; it just means that it hasn't been proven false. Of course, grandpa could also have bought this at a pawn shop in the 1930's on a haunch that someone important owned it, and the rest was a great story to tell the kids.
I'm sure at this point that it's being sold with the most honest of intentions, and that the sellers really want to believe this. I would too, if there was a couple hundred thousand dollars in potential gains on the line.
Somewhere I came across a great saying: buy the gun, not the story. Unless I had evidence to suggest otherwise, I'd heed the same advice here.
Mike