For sale; Cylinder head, P/N 303977, from 1956 Johnson Javelin 30HP RJE-18. Note factory parts catalog shows P/N 277419, $55.
One spark plug hole was Heli-coiled by previous owner and looks fine. Head in good condition and motor ran fine apparently, and I too had it running with no problem, but I am going through it and restoring it and in the process came across a new, old stock, never used, cylinder head.
This head should also fit some other vintage Johnson outboard models and years - but I couldn't tell you exactly which.
Buyer to pay any shipping.