If Sheldon already has the 3D print files for the shells, he could perhaps share the print files with someone who wants to print their own. Of course, this removes one small barrier to creating counterfeits. He might or might not want to take that risk.
I don't get the impression that he has files for the older pickups. It was a "maybe someday I'll do this" kind of thing. But perhaps then it would still be for themselves to create pickups to sell. But he likely would rather catch up with new orders.
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