That's a real shame. We are not helped here by the law that equates a 200-year-old single-shot antique with a firearm like a .50cal BMG long-range rifle.
I'm in the same boat with my two Canadian Sniders, one a family heirloom that saw service in 1871 during the last American invasion of Canada. Sure, I could sell two other guns so that I could legally shoot them, but I have no wish to have to lose two of my little collection to do so.
Having shot both pistols of a pair of Wogdon duellers I can testify that they make a Pedersoli repro feel like shooting a cap gun.