Missing exterior door trim piece.

[all4mom]

Just noticed that the little square of black plastic molding above my passenger side side mirror is gone. Not sure how THAT happened; hopefully parts aren't just beginning to fly off randomly! Also, no idea where I'd find a replacement part short of going to the dealership and trying to order a "new" one. Is there a way to determine if a 2008 Yaris hatchback "carcass" is sitting in a salvage yard somewhere; if so, do any of them sell and ship parts online? I'll probably take Click and Clack's advice and just use black electrical tape to cover it up...