Do a search for local suppliers. Should be fairly easy to find a dealer. I used a local Chandlers and it's what they had in stock at the time. As for deviation, I had none when I initially fitted it and I had a vhf just above it, a gps and a depth finder all above. Then I bought an 8 spoke SS steering wheel and had loads of problems and would swing violently one way then the other as I turned. I took this into work and demagged it in a machine I have in the workshop and that cured the problem.
In my new RIB I'm thinking of not fitting a permanent compass but keeping a hand held one for emergancies and using GPS as my primary nav. I think that accurate compass use is pretty usless on a RIB espetially in rough wether.
Hope this helps.
Looks Slow but is Fast
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