I wonder how hard it would be to bend some sheet metal or aluminum parts up for some of the plastic trim, or adapt older American/Classic metal trim? I've got a couple 61-63 American parts cars, saved some of the trim from my 63 Classic parts car, and have a 68 American parts car. If I get a Hornet or Gremlin later I just might try adapting or making metal interior trim parts.
I agree it's tempting! I think it might be a harder task than it appears. The curves are subtle though. In my quest for workable trim I took home a lot of pieces that looked close but were far off; concords, later hornets, wagons, eagles... all essentially the same design but completely unfittable.
They are all simple, open shapes, with a good mold you could probably form them from sheet in an oven. A bit too much investment for me!