Seadeck is very expensive, I'm looking into this myself at the moment. there are other products out there, Ultralon is one that stands out. Available in Z-Tread or octagrip, lots of places sell it, but be careful with sizing, sizes offered vary widely. I found one place online that was selling 2030 x 1050 sheets of either for about $230 each. All of them come with adhesive backing, you'll need to sand down your non-skid to a smooth surface first, as far as I know. All of them are better looking than non-skid white fibreglass, which shows every little mark and stain.