Help with a Halloween costume!!! Please!!?

For halloween I am being a go go girl. I already have the boots so i just need the dress, but the problem is that a lot of costume stores sell it with the boots or are to short and tight and a lot are way to overpriced. I need a go go girl dress that is $25 the most and is not too inapropriate. I am only 11, but dont find a childrens costume. I no this a lot to ask for, but remember if you win you get ten points!!! Thanks sooo much! (links are appreciated)