Kiwi, Old trick ,the ring bolts, I use them all the time to lash blocks too, you can make them any size by using different size screw drivers as a mold, copper wire is best or maybe I should say, easiest to use and solder (Just saw I didn't spell check that last one "Blast") I use brass (When I can get them) split pins for the working ones, as they don't pull out under a load, and just a "u" shaped bit of wire on the ones that are just for show
Right time to show how I made the hull I'm using a corn flake box for the construction so the keel, stem and stern posts will be laminated of 3 bits of card and unlike a wooden keel will not have a keelson ...I use a lot of paper clips (Marvelous invention for model boaters very under rated)as clamps, you can bend them into all kinds of shapes ---I'm not going to try to make this neat and tidy but show my way of doing it I 32nd or 64th ply or how you can make ships boats (A4 stiff paper)
Remember this hull will be built with out frames or a mold ,,,Frames if needed can be added laterJimmy