I have a set of once-used rear seat covers made by Shear Comfort from my Nissan Titan Crew Cab. Seat configuration: 40/60 Split Back with Pullout Armrest and Adjustable Headrests. Leatherette charcoal grey.
Will fit 2004-2013 models, and possibly 2014 models.
$150 for the set.
http://www.shearcomfort.com/