u have to go to the dealer......they will charge u 80 bucks....yes it is a racket but that is how they make a free 80 bucks at least once every 2-3 days at most dealers......
so u have to think.......call dealer and see what exact price will b in ur area....then go price aftermarket radio....might b worth just buying aftermarket radio........don't forget u will need wiring harness adapters if u go that route ...good luck