FRP top trim parts are all discontinued. The ABS deep draw components on the B pillar / rollbare have their weak spots. You might find some used ones in a better condition than yours, but they'll have issues too.
You might have luck for doorcards and sidewall trims. Those can also be reproduced fairly easy, either DIY or by a professional trim shop, which can even apply plastic or fabric cover.
Known issues on the ABS trim pieces are:
- Top layer gets brittle and comes off like sand
- Cracks
- B pillar trim is worn at the side facing to front, due to rubbing when getting in and out.
I refurbished mine:
- Plaster cracks from the rear, using 2 component 5min epoxy glue and glass filament mat (roughen a bit and degrease)
- Fill cracks front using special plastic bondo
- Sand down the top layer coming off
- Repaint using special plastic adhesion promotor, plastic structure spray and acrylic paint
Painting plastic in a durable way is hard in a DIY approach. I was quite successful and it came out looking nice.
But at some points, in particular where the seatbelt buckle hits, its comes off.
May be worth to give it to a professional.
Good luck
Ralf