I have a set of once-used rear seat covers made by Shear Comfort from my Nissan Titan Crew Taxi. Seat setup: 40/60 Split Back with Pullout Armrest and also Adjustable Headrests. Leatherette charcoal dirty.
Will fit 2004-2013 designs, as well as perhaps 2014 designs.
$125 for the set.
http://www.shearcomfort.com/.