I've never known of the seat skins being sold to recover your OEM seat. You pretty much have to find the seat you need at a salvage yard and it's a quick R & R to unbolt and install a replacement seat. Finding a slate gray & vanilla seat will certainly be a challenge as that is a rare one . . . Your other option is to go to an auto upholstery shop and have them recover your OEM seat.

If the leather is just kind of cracked and worn . . . there are leather refinishing guys who really work magic and can refinish leather to like new condition. You might want to check on that option too . . . In fact I see you are in Ft. Lauderdale. There is a leather refinishing guy right nearby. I'll find his information and post it here for you . . .

This is the guy . . . http://www.qualityleatherrepair.com/ Be sure to look at the "photos" section on his website . . . Amazing work!

Good luck!