If you have a Ace Hardware or TrueValue Hardware in your area, pull the lock and maybe one of the screws and go to the hardware store and try to find a screw that will fit. Also, if you have an old time hardware store in your area, they may have screw too. If you find a screw with the correct thread size, but is too long but none short enough, buy the long one and a nut to fit the screw. Put the nut on the screw above the extra length and cut off the extra length, touch up the cut off end with a file or sharpening stone and unscrew the nut and you should be good to go. I needed to replace a metric screw on an old Ardesa muzzleloader and that is what I did. In that case I only could find a correct thread with a allen wrench type head. I bought it and cut to length and then ground down the allen head and cut regular screw slot. A little time and very little investment. If the screw is the chimed or silver screw, use a little cold blue to change it to the normal black.
