cool, hope you get it worked out. what kind of shape is it in? got any pics?
nice! that would be a blast to have in good working order
my brother was just looking into an old winchester brand slide/pump 22 he used to use many years ago ( with an octagonal bbl) and his jaw dropped when he saw what they are going for now. used alot in arcades they are very much in demand now, depending on mdl. and astoundingly accurate. for the part use the net. midwayusa.com, gun parts .com. try seeing if anything comes up by entering the mfg and any info would help send pics and ser#. as for smiths any should be able, sounds like a simple part replacement, as those things were realy built to last.
try putting a piece of scotch tape over the firing pin hole and dry fire it if able and see if it puts a hole in the tape. and check out the bbl for rust/obstructions cuz if severely corroded it may not be worth the $$, but would be some nice wall art. any idea when last fired and by who and if able talk to them.

