http://www.truckandcarshop.com/trucks47_59/t47_content1.html, http://www.lmctruck.com/, https://shop.classicindustries.com/1947-2008_chevrolet_and_gmc_truck_parts, http://www.oldchevytrucks.com/. There are others but these will give you an idea of what is available. Generally cost is pretty close among all the vendors. If your original seat cover is still there (albeit worn) it can be used by a local shop as a pattern to make a new cover (what I'll be doing with my '58 Apache when the time comes as nobody makes an accurate patterned seat cover to match my original). Good luck!