I'm not sure about the level of restoration you're trying to attain, but I have a used GTS seat that I picked up on Ebay a few months back. I BELIEVE it to be their Sebring model in leather.
I haven't tried it for fitment yet, but it comes with headrest, mounting hardware, and back support air bladder thingy(not sure whether it is functional or not).
This seat is beautifully crafted, however it has a VERY slight area where you can see the driver's side seatbelt wore against it for a short time. It has 2 very small dimples on the seat cushion where it looks like someone set a box on it for a while. These might fade as the leather stretches with use??? Finally, one of the small plastic grommets that goes around the headrest post is cracked. This would be an easy fix by any upholstery shop.
I have tried to capture these small flaws in the pics. Anyways, I'd sell this seat for $700 plus shipping/delivery if you don't require a blemish-free new seat. Brand new, this seat goes for around $1200.
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