I've been away from punting for quite a few years and it seems very hard to locate parlours on the web. Presumably legal issues? I would very much appreciate any pointers to good establishments in or around the Gloucester area, perhaps as far as Bristol.
Assuming that it is not really the massage that you are looking for, your best bet probably is Bristol. I can recommend Central Massage. There used to be 3 establishments openly advertizing themselves as brothels, but they may have closed.