I'm planning on doing the costume myself. Pauline's gown actually looks pretty simple and I've got patterns on the way that hopefully will have some good instructions. Plus I have two friends in the SCA (non-local unfortunately) that I can ask for tips.
Actually originally I was going to have one of them do the costume herself, but I don't think I can afford that.
I am planning on getting the corset custom made though from a real corsetiere.