There is a wide range in prices, just for the airport card - Apple part is 661-5593
$390 (!) http://www.memory4less.com/m4l_itemd...FYGK4AodI3sR2w
And - these prices are for the US/Can/Latin America. I guess that you are not one of those? The card would be different for other world regions, and might be only found locally, but I don't know that for sure. One region's card will not work in other regions.
Do you know where your airport card is located inside your MBPro?
Are you anywhere close to an Apple Store (not a reseller)?