These are standard UK, and more commonly used in France too now.
There are 16amp and 32amp. (16amp more common)
The marina post will have a trip/RCD, I'd still have something at the boat end as well.
Your local electrical wholesaler will have the sep. plugs and sockets.
I might have plugs/sockets already made up, but will be on 2.5mm sq cable for 32 amp.
NB Try not to use standard PVC cable - get "Arctic" grade, which has a greater temp range.