if its totally stripped w/ no threads you can re-tap it. you'll have to go up one size on your screw. I've done this many times. its easy. tap and die setes are reasonably priced. or you might be able to clean the threads up if there not to damaged. and make sure you use some lock tight. if your not comfortable doing this. I'd advise you to take it to a gun smith. they can re-tap pretty cheap.