Marc, are you talking Damascus barrels or fluid steel? Can't help you with Damascus, but if you need to shoot steel and want to reload, Alliant offers at least one 1 1/8 oz load at 9,000 psi; lighter shot charges at reduced pressure. So as long as you don't shoot steel shot larger than #4 through chokes tighter than mod, and work up some of those low pressure reloads, there shouldn't be any reason why a vintage gun won't handle them. When and if we get Bismuth shot available again, you'll probably see even lower pressure loads available, with shot that's even more barrel-friendly. So I can't see that you're going to be out of business, even if MN were to ban lead for all upland hunting.
Ted, I realize SD isn't much for ruffed grouse--which is why I mentioned your neighboring state in the other direction (WI). As for people not traveling to hunt . . . east of the Mississippi, with the exception of WI and MI, and maybe from PA on north, virtually anyone who wants to hunt much in the way of wild upland birds is going to have to travel. It's been 10 years now since I guided pheasant hunters here in Iowa, but everyone I guided came from somewhere east of us, and hardly any of them did any wild bird hunting at home--simply because there wasn't much available to them.
