I know of a few really high end shops, and I know of some VERY reasonably priced shops.
Ogden Top and Trim is premium level my buddies Father takes all his Ferrari's to.
Rigg's Brothers is more the common man prices that does AWESOME work very cheap.
I just had them do my 442 seats at the St Charles location.
I brought him the material and buns, and he put the front seats together for me for $325.
Spring repairs, and all that jazz with it.
I'm having him redo my 78 Camaro rear seats to match the 2002 SS front seats I bought
and install it all as well. He did such good work, I'm sticking with him.