JC Whitney may have it, possibly Perfectfit.com, and when you have the old off check the fiberglass seam as I had some water leaks where the seam had some flaws.
Google "Trim-Loc". There are many suppliers including eBay. I used the JC Whitney stuff because they sell in short rolls, but it was slightly too wide and I needed to carefully squeeze it down in my vice before installation to make it grip.