…..and lurking at the bottom of the "deck fittings" page is PW8j, a detachable turnbuckle, but using that will probably depend on the particular eyebolt being used.
Is the mast deck stepped or plugged into a fitting that goes deep into the hull? A deck stepped mast has different requirements to a keel stepped one because the forces going through it are much greater. I have a tendency to use stainless wire staples for that particular job. Some like chain plates, either brass angle with a row of holes for the rigging hook and screwed to the deck, or a flat plate screwed to the hull side with much the same effect.
Edited By Malcolm Frary on 01/08/2018 10:38:12