I put in a 220V system in my new boat, much larger than a Sabre, using a domestic consumer unit with an RCD and MCBs on each circuit, bringing the power in via a galvanic isolator, to reduce the danger of stray current corrosion. I am considering fitting similar to my Sabre. For that I would just use a water resistant garage or caravan consumer unit with two MCBs like this:
https://www.ebay.co.uk/itm/264454641821. I'd still install a galvanic isolator, though. Use arctic spec. flex to connect to sockets, not domestic twin and earth.