Cinderella Dresses Best Place To Find A Cinderella-like Dress Within 2 Weeks?

Best place to find a Cinderella-like dress within 2 weeks? - cinderella dresses

I do not want me as a Cinderella in my birthday dress (theme to go has come as something beginning with C. clothed)
I was able to help 30 € for a team, but my mother. I need to find a suitable dress, they can not (mail order) test and can not be too expensive. To suggest the stores are only in the United Kingdom and possibly in the southeast.
Thank you.