I just purchased a set of screwdrivers made to fit a specific gun from Grace Usa. I discovered they will grind a custom set of screwdrivers to fit any gun. It is not a close fit it is an exact fit! You may send them the screws or give them the exact dimensions. The cost is ten dollars per screwdriver including shipping and return of your screws. If you dislike the play in replaceable tip drivers like I do, and want to keep your screw heads perfect it's well worth it. http://www.graceusaguntools.com
FYI; Tom