My very old house has decided to spring a leak in one of the shower faucets. Unfortunately, it's the hot one - when you turn on the hot water, more water comes out the faucet handle then out the tub spout! (Probably an exaggeration, but that's what it feels like.) I went to pull the stem valve to replace it or the washer only to discover that the 21/32 tub socket wrench is too small and the 27/32 tub socket wrench is too big. I've not been able to find a tub socket wrench in between. The local plumbing supply store tells me that some manufacturers have their own specific tools, but I can't find a name printed anywhere. From the looks of it, the bathroom was probably renovated last in the 50's (all pinkish). It's up for a gut job hopefully mid-next year, so I don't want to damage too much in the process, but I would like to stop burning my hand on the faucet. Any suggestions on how I can get the faucet stem out?

thank you!