You try Parts Heaven in Newark? (if you live in the Bay Area). They collect a lot of Porsche Junkers.
You can also get new leather covers on eBay and have them
installed at an upholstery shop.
I have a pair of black seats out of a 55K mile 2004 std. I been wanting to get these sold but haven't actually listed. I can be contacted at linaresr "at" san.rr.com. I can email pictures. They are power backs with manual everything else and non-sport. I'm in San Diego and can arrange to meet somewhere if in So Cal. if you decide you want them. The only thing missing is the seat belt receptacles. I'm using them on my current 996 Euro GT3 replicas.