It turns out that Tumacs makes the frames as well and they only work with dealers. I think I'll just bite the bullet...https://www.tumacscovers.com/
They offer 3 materials
Sur Last is the one that Bennington uses
Great Lakes Skipper ,has some Bennington OEM parts .
Closeout Prices on OEM Boat Parts at Great Lakes Skipper. We have a Large Selection of the OEM Replacement Boat Parts you Need in Stock and Ready to Ship. | Category: Bennington Pontoon Boatswww.greatlakesskipper.com