These ones sound like they could suit you, because you mentioned you had a red and silver beaded prom dress, and the silver ankle strap is pretty cute.
Hi, I am a royal customer of this store, I believe you could find a style you like here: 1)They have quite complete colors, so whatever you want. 2)All styles could be made into flats(because they could do different heels height :) You could message me if any questions. My skype is techfirst ^___^
Try ebay: If not go into town and look or go onto every shop website you can think of.