Knocked my brand new Black Project Epic Wave (20cm slot box) fin out 10m off the beach in front of the outfall pipe at Mettams last Friday. If by some miracle it washes up in a storm, is not totally shagged, someone finds it and decides not to keep it please let me know. I am happy to buy it back with beer/wine.
So really, you are appealing to alcoholics who like long walks on the beach and who aren't arseeholes who would keep it themselves. I might go have a look for you.