The part cost according to the estimate I received from a body shop was $125.00, assuming it was just that one part that was bad:
Door,Charging Port LT 103854800F $125.00
I think there's another part number, 1038548-88-G that is the door + the mechanical and assembly parts and I would assume that is a good bit more. There's one on E-bay right now for $155, completely rough guess maybe $350? Plus an hour of labor, my guess is if they charge you the total comes in at just a hair under $500 if they replace the whole assembly, $250 if it's just the door. Let me know if I'm close!