the little mermaid costume?

so me and my two friends want to each be a disney princess.
jasmine,cinderella, and ariel.
jasmine and cinderella have simple costumes.. that are easy to find.
but ariel has a fin!
im thinking of wearing one of the dresses she wears in the movie.
if any of you remmeber.
should i get it made?? or can someone help me findd it?
thanks so much guys!

example:
static.flickr.com/3574/3337340983_ab5b8124dc.jpg

http://store.costumecity.com/littlemermaid.html