I've been to 2 different landscaping places, and they didn't have any of the stuff. I found some on-line at Lowes, but when I was at the store, they told me they put all that stuff away for the season.
One of the professors in the Horticulture department up the hall from me is installing a pond in a few weeks as a class project, he said he'd get me some. He showed me what they use, it doesn't look that similar, just sheets of thick rubber, very flexible. The skirts I have from my truck at more of a stiff vinyl. I may have to use it anyway, until I can find something better.
There's an interior shop about an hour from me, they do great work, I'm gonna have them make me a new headliner since that's the only interior part I don't have. I'm hoping they'll have something.