These are like hen's teeth, but I see them come up once in a while on the auction sites. With a part number from Gary, you can search places like rearcounter.com or greensalescompany.com
I've had good results repairing them with fiberglass mesh "painted" over with plastic epoxy on the rear of the trim parts, both for the pillar and door trim. I clean and rough both sides of the crack (and even full breaks), lay down about an inch on both sides with the fiberglass mesh I use for drywall seams, and then then lay the epoxy over that, sometimes with a piece of aluminum flat bar as a backplate.
Although I've used JB Weld plastic epoxy in a pinch, I've found the Polyvance products a bit easier to use and is of excellent quality.
Planning to head out there tomorrow if possible and grab some ac dash parts. I think I posted in your 'want' thread the other day regarding these. Email me or add to that thread anything (with specifics) you are looking for and I'll add it to my list.
I know it's a long shot but if you use the app Wunderlist, let me know and I can share my jy list.
Daily driver: 'Camano' 1986 F250 Supercab XLT Lariat 460/C6
Work truck: 'Chanute' 1980 F350 C&C 400/T18 - Gin Pole
Various parts trucks