Point of View
From my own point of view, I would go with plugging the hole with a soft steel 6-48 "plug" and re-drilling it in the correct location. To me, if you try to redrill the existing hole, there is large possibilities of the drill following the old hole and breaking off in the hole and then there is a REAL mess to clean up. Ideally the plug could be silver soldered in place but then do you really want to heat the receiver? I would suggest using Permanent Grade Lock-Tite on the plug when you plug the hole. That should hold it in place while the new hole is drilled and tapped.
Just my $0.02.
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Every problem can be solved through the proper application of explosives, duct tape, teflon, WD-40, or any combo of the aforementioned items.