organic hard surf wax?
Carnauba wax is a high-melting wax that should be suitable. In the Wikipedia article cited,
"Carnauba wax can produce a glossy finish... It was commonly used in its purest form as a coating on speedboat hulls in the early 1960s to enhance speed and aid in handling in salt water environments. It is also the main ingredient in surfboard wax, combined with coconut oil."