Is a Museum Replicas "Medium", the bust is around 38" or so (and is the smallest part of the dress). I ordered a medium and they sent me something with a medium tag but it was HUGE (it would have fit Brian). A tailoring friend took it in to its current 38" state. She also added a loop of pearls at the bottom of the skirt train, so that I could walk with it without it dragging - its quite long.

I think I paid around $140 for it. Brian spent about $30 on materials for the crown (and a ton of time making it), so I think I'd be happy to get around $125 or so for them both (shipping would be separate). I'll throw in the shoes and ears too - they cost next to nothing and aren't totally accurate, but they worked well enough (size 8.5 slip ons).