People using Macs portable in intense moisture environment may have that issue. If you are buying a new Mac as you have described, you may just go ahead and buy without a doubt. Regarding replacement of the display, the cost gonna be couple of hundreds below what you have mentioned. Yet, there will be third parties selling the same specs screen in a cheaper price (which is a good thing).
Do not worry. I suggest you buying your Mac from a competitive market that may even do not charge tax if their business is not in your state. Try [http://amzn.to/1RuGKbe|this] if it helps.