We searched all over for seat covers for our previous Class A. Found there weren't options, just the ones that the big camping store sells were the only ones. They weren't too great, really crappy on the back of the seat. We returned them and had the seats reupholstered, which cost a small fortune. Sadly, Flexsteel does not sell skins for their seats.
Just an idea: You might consider trying to find some decent seats at a RV salvage place. Good luck!
Bad decisions make great stories!