There are others who do this but here is his facebook page if you are close to Dallas. His name is Pedro.
https://www.facebook.com/pgauto.upholstery/
Shop name is PG Auto UpholsteryHis shop address is 3402 N Beach St, Ste B, Haltom City, Texas 76111.
I don't know for sure but I think he has done some cars for some local awards shows and if you check his photos on his fbook page some of the custom work he has done on C-10's and other Square body chevy's just looks second to none.
He has some photos of various squares in various sizes and shapes... single cabs, crew cabs, a full top 73'ish blazer...
Links to has facebook photo page.
https://www.facebook.com/pg/pgauto.upholstery/photos/?ref=page_internal.
He quoted me a price of 325 about a year ago to fix the cracks in the padding and receover with Vinyl. Honestly, my dash is just destroyed (and he's seen pictures of it, lol.)
I've held off because right now I am focusing on the chassis and power train so the dash is the furthest thing away. In fact it's probably going to be one of the final things I install, and I hate to tie money up in that now when I can use it on other things. Also I am unsure if I am going to do something with the audio stuff, like larger speaker's in the dash, or figure out a way to mount an android head unit in, and that might require some changes in the dash structure (trying to avoid it but most options I see might necessitate it).
From what I have learned since then I figure the door panels will probably be about just as much if nothing custom is done but I think it will be worth it. I do think I am going to add some of the 3/4 MDF panels to mount a set of component speakers in the area above the pockets but but if I do that I am going to want the panels and things to be under the vinyl and have it so the speaker grills are inset, so the customization might cost a little extra. I am probably going to do the woodwork on the panel, mount by switches in the panel, and have it ready to be upholstered. That part is just a matter of wood shaping and attaching (will just use some stainless panel screws from the back - side, and then I am going to make my own alluminum inserts on the upper rectangle part and around the door handle use a combination of the OEM handle surround and make a micro-suede panel where GM put those carpeted pieces.