Had a customer brought this into the shop yesterday. It will no longer shoot, as the firing pin has somehow curved itself. As far as I can determine it is a Mark I, serial # 34507. No idea who chromed it or when, it still is set up for .455. The question, can not find a hammer/ firing pin, Numrich Arms has one for a Mark III, and I found other non Mark I hammers on other web sites, will it work? Beyond that, I have no idea, except taking my torch and heating the pin to a minimum to re-straighten it, and I realize that opens up a whole new set of potential problems. Ideas? Suggestions? Other parts suppliers?