Dessy suede rose dress desperately needed!

My best friend is getting married next May and wants her bridesmaids to wear dresses in Dessy's shade "suede rose". The problem is, I'm a student and really can't afford the price tag of a Dessy dress! My friend is awesome - she'd never demand I spend money that I haven't got, and has said that anything that's a similar colour will be fine, but I really want her day to be exactly how she wants it - we've been friends since we were 4 and she means the world to me. Plus there's the fact that the other 2 bridesmaids will probably be buying Dessy dresses, and I don't want to stand out as the poor friend in the knock-off dress!! I'm desperately searching around for anyone selling a pre-owned dress in the right colour and size (I'm a UK 10 - 12), and thought it was worth a try appealing on here.