This may be a dumb question and if so I am sure someone will inform me of such.
But, why couldn't you just find a washer that was just the right size and place it between the guard and stock with the screw running through it? If you are looking for "authentic" or are trying to keep your rifle legal for matches of course the washer idea is out. But, to simply tighten up the fit I fail to see why this would not work.

daveboy