Yup. That's what I figured would happen.
Here's the place the 928 guys go to for world class upholstery and interior restoration. Bob Budd is hands down the best guy around. His work isn't limited to just 928's. He does all kinds of Porsche work. You can send your seats to him and he'll do an amazing job. My guess is in the ballpark of $1,800 or less per seat.
Porsche Interior Restoration Leather Craftsman Classic 9 Leather
Take some time to look through his website and see what quality of work he does.
Edit: He also makes a seat cover that you can install yourself - that may be the way to go.