I believe cleveland tool sells back seat seat rests in a 60/40 configuration with the headrest built in. You can also get two 40 parts to keep the gap between seats if you like.
I've got them in my 10. I have the 60/40 split seats. Classic Aero. Great addition if you have family members who like to fly and sleep. They have never been in the way regarding access to the luggage area in flight.