I know of 1 in a back yard near where I live in Brisbane,don''t think it's been in the water for at least 25 years..So that would give you an ideal of its condition.
My question why the hell would you even want one? If you need to get a keelboat get a flying 15 if you want to race ,or a Diamond 30 you can get a **** hot glass one for $5000-$8000 twin trapeze and walk all over a tempest. If you want a decent fast centerboarder go a 505 or a sharpie