Your best bet is to have someone dovetail the slide and put in a new sight.
I know others here say they like staked on sights and have had good luck with them but I have shot many a staked on Colt sight off. So I don't think it is worth fooling with them.
After loosing a few, I first staked them in place, then had my nephew get out his mig welder and just touch the stake where it comes thru inside the slide. Nothing got hot, and never lost a front blade after that. But I would prefer a dovetail slot.