Are these parts going to be hard/impossible to find?

[Jobe72]

I just picked up a 72 GMC Sierra LWB. It is medium green/white with a Medium green/saddle brown interior...I know it's funky!

Is this a strange combo or what? Brown glove box and cluster, pad and dash, seat and carpet...full cheyenne package with the headliner and all.

Anyway, need to put shoulder belts in and it's missing the ashtray.

Any chance in hell I will find original brown shoulder belts?
Any chance in hell I can find a medium green ashtray?

The truck is very original and I'd like to keep it that way as much as possible.

Here is a quick photo I snapped with my phone for reference.

Thanks!