Auto body stamping dies

I was going to inquire of the members who've been in the auto industry: How do these aftermarket body panel mfrs. get the dies to stamp the parts from?
I have been under the mistaken impression that nothing short of a big company would have the pockets to have employee's build a big stamping die...that surely the repro guys must have had some back channel connection with the person at GM/Ford/Chrysler that was in charge when they changed model years, and would go in and buy out all the...​