Our family has a M1816 Springfield musket, dated 1837. It's in good condition but it's missing a part. It was converted to percussion cap, french method, it did not have the flash hole welded closed. Instead the hole is threaded, and at one time a screw plug must of been installed. The screw pug is missing and I'd like to find a replacement. It's threaded with an oddball screw pitch, perhaps 10-28. A photo I saw showed a pan headed screw plug. Any suggestions on finding a part, even if its a repro? Also is there a chance this musket could be fired again?, after an inspection by a smith, of course!