WW243 I was thinking about filling it with epoxy resin. Actually just a two part solution clear drying. That stuff drys hard and tough, is suitable for sanding and drilling and cheap and available.
Doesn't look so nice but no one will see - the other option would be to peen brass into the hole and drill it out. Looks classier I guess. I doubt the epoxy would ever fail though
Sharptonn uses the sleeve of a pop rivet for the misshapen tang holes...not sure of his process, or if would be relevant for your purposes...sounds like epoxy will work.