Look for a local general aviation F.B.O. in an airport your area, Call and ask the parts manager to order one for you. Get a price first!
KIWL stated that a magnet won't stick to cast iron. What kind of magnet does he have.
What kind of magnets do you use?
I came across this on an Azmut yacht. I was told that the coating was not varnish but lacquer.
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