one of those questions i get emailed regularly by people wanting to start off with something in latex is what to get and where to get it?
i generally warn them off molded items unless is something basic like gloves or a skirt. then the Q arises of where? ebay is a great source as its an international market place and with the dollar very strong against the pound you can get a really good deal.
one ebay store that has a quality range of clothes is Yap 295 - from basic stockings to full catsuits with a few items in between.
i've not ordered from them yet but they have good feedback and the catsuits start at £99 if its your size. so that's about 150$.
another trick i've found when wanting to get something for the best price on ebay is to use bid groups at Auction Sniper. essentially you make all the snipes as normal of the same product be it a catsuit or a digital camera. then you move them into a bid group and when you win the item at the right price the remainder of the snipes are cleared.