I have really been trying to research this to see what's available and what others have done. Seems the the best solution, as in most cases, is for the DW & I to make our own. Have to do more research to see just what parts are available at what price. I think I can buy an inexpensive canopy with the X cross members and buy some additional fiberglass poles to frame the outer edges. Have the DW sew "pockets" to hold the frame poles in position. Then get some sturdier multi piece poles for uprights, which will angle back to the running boards.
Sounds simple. Just a matter to measure, find the parts and get time to do all this.
Always looking to help and/or ideas.

Something similar to this, but on a Ford Econoline. Upright or diagonal poles would connect to the corners (be further apart).