There are bits available to drill out PVC slip fittings. Have some, haven't actually used one yet. Not sure how reliable they are, especially if the end of the pipe is slanted or jagged; I would recommend caution and carefully keeping the drill straight.
If it were to start going wrong, e.g. drill motor jumps around and the bit wants to go sideways, back off and rig some sort of hard guide for the shaft. Might use a Dremel tool. And wear a mask, goggles, have a vacuum going to catch the little PVC shaving snowstorm.
I'd think that extra care and (as a brainstorm) possibly some 'filler' cement (mix clean PVC shavings with cement to build up the fitting if needed, thin layers then give it time to harden)? might be needed.
Jones Stephens Corp J44-150 Jones Stephens 1-1/2" Ram Bit Socket Saver
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