I found a pristine .56SB hanging on a gunsmith's wall last year, that I was able to buy for $50, since they're no longer popular in this area. (They were once upon a time the only muzzleloader allowed by law in my state for deer)
I use 28ga shotcups & an overshot wad in it.
I've since won a gunbroker auction for a likewise-pristine .54 Renegade barrel that was a drop-in, so now have a 2-barrel set.
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