I made a wrap around comb pad from a piece of 5mm neoprene wader material. It overlaps at the comb and cheek for a double-height gain - a measured 8mm rise. The pad had a tendency to slip forward with recoil, so I put double-sticky cellophane tape top and bottom. This stopped any recoil movement. The overlap wrap is held by Velcro, Goop cemented in place, which took a bit of trial and error to judge.
To help avoid mistakes, I first made a construction paper pattern.
