Steve, from here all I can say is a fellow I know bought a used original muzzleloader, the bores were somewhat pitted and rusty but they looked serviceable. His first load was none to difficult to load but after a only a few shots that bore and the resulting fowling was tearing up his wadding, both the over-powder and over-shot wads and he tried both 2FG and 3FG.
I saw a pristine William Moore built muzzleloader, which is on par with the Hollis & Sheath, sell for $1,500 a few years back but that was a 12 gauge and in pristine never been shot condition. There is also a real nice unmarked muzzleloader but it has Birmingham proof marks, a 14 gauge selling for around $1,500.00 at Dixie but that gun has been there over a couple of years.