C-racer do a range of farkles for the current model SV, including a seat available in two colour options.
It looks much flatter and more padded than the original.
Unfortunately it has stitching therefore (like all stitched seats) it isn't waterproof.
https://c-racer.com/store/scrsv-bbsw...own-black.html
https://c-racer.com/store/scrsv-blsw...ack-black.html