Grounding probe!

[Canadian Man]

Simon,
I dont know if stainless steel will cut it as an item you can put in a salt environment.
I don't have any first had experience but I do believe it will rust.

I have heard of going to radio shack and getting conductive foam of some sort.

As far as your wireing goes to make a slick unit take a dremel tool and cut the Power parts off the cord and just leave the grounding prong.

Or you could wire it into a diy light set up and just attach it to the ground somewhere there but, you may not have such an option.