Door panels from SMS run about $900. Have to have the seats made up by a local shop from SMS material if you want orig material and pattern, not cheap. The seat upholstery is expensive to have done since they are tuck and roll and it takes more time ($s), you can cheat on it with just stitched seams rather than tuck and droll and ii’s cheaper and comes out pretty good. Don’t know anyone who makes up 62 upholstery for the Olds. Also, Buick Skylark sets are available and I believe they fit, different patterns someone here may know better.
Ames Performance sells upholstery for the Tempest, which also fits. Of course, none of those options will be correct.
It cost me just under $900 for door and rear quarter panels for my 67 Delta from SMS, so that number is accurate as of a month ago. I also got all the turquoise upholstery materials and headliner for the 67 from them as well. Certainly not cheap, but where else are you going to get this stuff. Despite horror stories about service, my materials arrived exactly ten days after ordering. Door panels are supposed to be done in another month or so.