+1 on a fab shop. It may not be cheap but it will do what you need. Shop rates are probably around $100/hr. A good fib guy should be able to crank one out in an hour or so if you give him a drawing to work from.
I would also look for an owners group and ask questions there.
2015 Seaark 1872 MV CC Etec-90
Helix 12 CHIRP SI, HB 1199, MinnKota Riptide ST80/i-pilot Link, Bob's Hydraulic
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