I often make screws for the original locks where the screw threads are unique. I recently made two such screws for an original gunlock under the "shade tree' at Schoenbrunn, Ohio with no electricity or modern tooling at all. Not really a difficult job if you use 18th c tools and materials, but probably a lot more difficult with modern machines. Let me know, maybe we could make this into a tutorial of HDTDT of making odd sized screw threads.
Jim