Do you have one serviceable one?
Note: I can't tell much from the drawing so I'm kinda just guessing here. Is the firing pin the sort of thing that you could take to a machinist/gun smith and have made? Might be a bit easier. If you order an off sized pair, you may still need a machinist/gun smith anyway.
I would also recommend asking one of the moderators move this to the Gunsmithing forum, better target audience.