One option you may try is to get a hold of a local used car parts/scrap part yard, and see if you can find one that way. other than that it's a dealer item only, as far as i know. when you called your dealer to inquire about the part, did they ask you for your VIN#? if not they may have just priced you the most expensive one, there are 3 different one's it could be and the $265 is the most expensive. and as far as the labor..i would bet they are charging you 3hrs @ $75 an hr. to install the switch, which seems like alot, but i don't work with labor times very often to know for sure. i suggest you call a different dealer and see what kinda price quote you get from them. I couldn't verify the part being on back order, can do that tomorrow at work. i can tell you, as of Thurs. we had 1 in stock.
hope this helps