I think the original is about 3/16". Mine is a little torqued too. Buzz has one that's 1/4" if you wand a beefer one.

:: My mast base is in tough shape and Id like to replace
:: it. The hinge is bent and is hard to deal with. My
:: previous boat a J 22 had a much better base. Has anyone
:: replaced this flimsy base with a better one from another
:: class?