I'd take it to a gunsmith who has the correct drills and easy outs as if the hole gets wrecked it will cost more. I know people who have drilled the screw and used a small torx bit ans an easy out but it would not be my first choice as the top of the screw is probably not busted of flat and would be hard to drill an centered hole ( though it could be drilled from the inside but that risks ruining the hole on the other side if the drill bit runs a bit.)