Maybe you could modify this. I made this log for a handboard I shaped (a handboard is a very small surfboard, so-to-speak, for bodysurfing. It helps to give lift when planing. It's about 18 inches long and a foot wide.

Anyway, I took a picture from the North Shore of Oahu (where the waves kill people) and modified it for my own "product."

Feel free to modify it again in however manner you like.