36', 12 yards, of 60" Sunbrella fabric, at about $40/yard is about $500. Depending on your sewing skills (or willingness to learn), the $800 more spent might be well worth it to you, especially if you can soon put your camper to use. https://www.sailrite.com/Fabrics/Marine-Fabric/Popular-Collection/Sunbrella-Marine,Sunbrella-PlusWithout windows it was $1,300. That is for 36' of 5' wide Sunbrella. I expected the material to cost that much by itself. We will add windows later in the year when he doesn't have so many boat jobs.
Then again, you have given yourself quite a hands-on education, and might just want to sew it yourself to be able to easily fix, and modify, the fabric of your camper.