I looked 7 years ago and some claimed to have them for $750, but I never actually tried and didn't really trust the information because it was coming across the counter from a flunky that couldn't confirm it.
Used are maybe $250-$500. Lowell howe has them if nobody else does.
There are some repros coming out of Scandanavia that are supposed to be wavy and not very accurate. Buyer beware on those.
When you are ready to go, don't let the people that are to do the replacement talk you into a new window gasket unless yours is really, obviously terrible, which they rarely are.
You can to the swap yourself using nothing but a butter knife (Jeff Ingraham showed me that one!) The existing gasket material is an incredibly efficient design and is reusable. Aftermarket stuff is BADDDD.
Write in when you get to that point, and I'll try to come up with some instructions/photos on windshield removal.