Some blue basketweave and pewter faux leather gator skin material for my RV-4 seats from fabrics.com. They may have something that fits the bill for you...
Check with Darby at Jacob's Upholstery in Spokane. They mostly do auto and furniture upholstering, but they also know aircraft fabric b/c, if I remember correctly, they do/did the upholstery in the Malibu jet prop conversions at Felts Field. They also have the coatings that can transform auto upholstery into burn-tested aircraft upholstery and can provide the burn certificates for it. This gives a lot more options in terms of fabric selection. They covered my Van's cushions for me.