Also head to the Chapel St Bazaar. If you have money to burn they have a couple of Prototype MPs that are hellishly expensive as well as a couple of MISB MP Hasbro Starscreams that are around the $400 mark. They may have had some more put on the shelf since I was there in July.
Pleasant Surprises is another one that has some cool stuff there https://www.facebook.com/pleasantsurprises/