I put some very thin nylon-covered neoprene over minicell thigh brace padding on one boat to improve grip when bare knees were wet. Wet minicell was slippery when rolling.
Thanks for the suggestion to try Joann Fabrics. There was one in my old stomping grounds; don't know about now, but maybe they'd ship some elsewhere.
Recreational Kayak Paddle
Kindle / iPad Cases