Dearborn has most of these parts but they are expensive.  also ebay is a good source.  have you ever thought of using vinyl die??  My interior was cream, salmon and burgundy and I used black a white vinyl die on the seats and door panels with fantastic success.

I tried to find some pix, I know I have some, but cant seem to find them.  When I was done they looked like they came off the show room floor in black and white.  I have had them like that for about 5 years, and there are now a few places that could be touched up but they are few and far between.  As long as you clean the vinyl really really well it works fantastic.