Gravedigger, Sawbones, Inventor, Demimondaine, Ratcatcher, Beggar--a fucked-up version of Tinker, Tailor, Soldier, Spy?
The pdf below has details on my gravedigger, sawbones, inventor, demimondaine, ratcatcher, and beggar backgrounds. Most of them are pretty specific in application, but the demimondaine could be used for any level of prostitute, from courtesan to three-penny upright or rent boy. You could roll on Random Harlot Table in the AD&D DMG to find out if you have an aged madame or saucy tart on your hands, if that tickles your fancy. Similarly, the sawbones is a solid basis for any sort of doctor, country healer, nurse, or combat medic you might want to make--but Gary never got around to making a random table for that.