If you or someone you know is an NRA member, they have access to experts.....there is a division that will answer members questions. You will need to provide EVERYTHING you know or can find about the firearm......even if you are not a gunsmith, you should be able to describe ANY markings on the gun. They may not have a lot of info on it but they may be able to give you some idea of where to begin. Another thing to try is a gun forum....someone there may know it.