A little known fact is that a great many "factory" products such as cruise, power windows and doors etc are in fact after market!!
My son in law manages a chain of auto electronics business in Portland Oregon called "Sounds on Wheels" in addition to the sounds--radios etc-- they do a large business with new car dealerships installing cruise, power door/window etc. He has eight vans and driver installers that do nothing but go to the new car dealers to install such items for the dealers who then sell them as "factory". They do in fact use exactly the same items from the same suppliers as would the factory--they just do it cheaper than if the dealer orders them done at the factory. --the dealer makes more money on the sale of the car/truck with the items if they are "after market" installed.
So if you shop the auto electronics/stereo installers there is likely one in your area doing the same thing.
Vaughn