If you know somebody that rides in parades in New Orleans, ask them if you can have their old costumes. They make a great "base" to build a traditional costume on. And they are made of really durable satin. With plenty of room to wear clothes under.

Many thanks to Chuck, Joanie, Sonny, and Layne for the fine suggestions!!! I showed your responses to my wife and now she's getting into the spirit too, which is important since she's the one who knows how to sew (I bet she'll make me learn).
Unfortunately we're not going to be able to make it down this year...but we're talking about next year...God willing. Meanwhile we're going to start working on those costumes and we plan to make them ourselves.
Thanks again folks! I always learn so much here.

Gonna put miters on em?

Only if they dress as bishops!