If you want cheap faces, hit up aliexpress and do a search. You can find all sorts of watches for under $5 each, usually in lots of 10 or more per design. They are inexpensive, made-in-China stuff, but for costume jewelry it's good.
My wife has me make her new watch bands for her Timex Expedition whenever the mood strikes her. Just about any watch with a standard removable band should have room between the pin and the watch face to slip in two to four strands of 550 cord.