a lot of the parts on these cars were off-the-shelf items for a variety of things---- A100 (van) seats, these delete plates, the de-clutching unit for the fan, to name a few. So if one is careful enough, have the part numbers and is patient, one can find these "specialized" parts pretty easily.
I agree most of the stuff is common. You ever take a real seat apart? They are not the same, close but not the same. When you order seat covers from legendary you have to tell them original seats or A100 seats