Well, as a Michigan resident who has gone through a similar situation, here's the deal. Just take the gun to the Sheriff or local police (whichever applies...outside city limits usually goes to the sheriff's office) and just tell them you want to register this old gun, and that the guy had no papers for it. They'll run the serial number and if it's not on their stolen list, they'll register it for you. I bought a barrel & extention for my broomhandle Mauser on e-Bay, and had to assemble the gun and take it in, since the serial number was on the extention, not the frame. I had no reciept or anything, but had no problems. Now I have one pistol with two registration cards...