I'm sure that the tooling is already paid off. Dies to punch holes in the panels could be a expense. Warehouse storage, back in 2008 when I bought new door panels for my 1973 dart swinger I was told that it was a 6-8 week wait because they didn't make the panels till a order was placed, if I remember correctly that's what they did for all of the mopar orders. Everybody on here knows that mopars are the most expensive car to restore. Again I saw new rear panels for the '67 - '69 A body convertible at classic industries. Apparently they are plastic and not covered, if I was doing a restore that's what I would do.