Have a 1973 Cutlass S, swivel seats, burgundy carpet and seats (front & back)
--Carpet needs replacement – need a source? What do I ask for
--Want to refresh the interior – need a source? What trim level do I ask for?

 

I doubt there's any one source for interior trim. The '73 and up Cutlasses are not supported in the aftermarket the way the '72 and earlier are. Whatever you need you'll have to either find used or make yourself.

Carpet, on the other hand, should be available from many places. I bought carpet for my '73 Custom Cruiser from this source:

http://www.varkmotors.com/

They have anything you might want in the correct material. You don't say if you have a two-door or a four-door, but I presume swivel seats were only available on two-doors. Here's Vark's page for 2-door '73 Cutlasses. They don't show "burgundy" as a factory color. Is that what it's officially called? Vark shows red and maroon. You can click on the color selector and see an image of a sample. If you're really concerned about match, you can have them send you swatches. But remember that if you're not recovering the seats and the seat covers are original, they'll have faded some over 40 years, and new carpeting of the correct color will probably not be an exact match.

http://www.varkmotors.com/1973-OLDSM...T_p_44576.html


Many people on here swear by SMS Fabrics or Legendary Interiors, but I've sometimes heard that service can be slow, which is probably a good sign as it means they're busy.

But, like I said, many places sell replacement carpet for your car. Just google "auto carpet" or something like that. I had good luck with Vark as described above. Exact match, high quality, fast delivery (about a week), good price with free shipping.

 

There is also www.stockinteriors.com

 

I just bought carpet for my Vista from ACC (through a distributor).