Not off an S/D but from my old 1/2 ton...bought them from Marathon Seat covers (
Marathon Seat Covers: Custom Truck, SUV Seat Cover specializing in Camo Seat Covers)
When I was shopping for covers I didnt want neoprene and this was one of the few places who sold non-neoprene seat covers (that were waterproof) that were not cheaply made.
The pattern I bought was MAX-4HD, I also had them sow in some more pockets for me
I am definately going to be getting another set for my OBS after christmas