SIms sup shape deck pads?

I struggled to find anything on the market available in europe fcs do some deck pads but there not that nice and normally don't have stock so ended up importing sheets of hydro turf from the usa.

Yup: www.gong-galaxy.com/categorie-produit/sup-fr/pads-sup-fr/

The "Camo" pads come in 200x60 sheets, you can cut them at your will
I would advise the diamond cut over the lines, it grips better.
The Camo pattern is great because it makes for invisible junctions between pad pieces. So you can cut the pad as you want to help applying it or fit a weird board shape with no worry of having the cuts visible.

They are good quality pads, with genuine 3M adhesive. They stick nicely wile being not too much a pain to remove if you want to change them, perform repairs, ...
However, like most pads, the surface is not sealed, that means water can stick to the open holes in the surface: it means it weighs a tad more wet than a sealed surface one like the hydroturfs, but if feels grippier. I weighted a fully wet pad at ~400g more than a dry one, for a ~ 8' board.

Also, the red ones fade a bit in the sun. But I was told all red pads did.

And the price is hard to beat... same price as a mere tailpad... you can combine colors and get creative :-)

For instance an easy pattern on my board (left)

Here is another Gongpad on a Hero 33" wide, strong and very comfortable underfoot.