M_Boats: Hello

Hello all. I'm a owner of a 1984 M17, recent purchase. It's missing a few things, standing n running rigging. No spreaders, centerboard gone, rudder cut off short. Are any measures available for these items? Thanks. Also I noticed the cast iron centerboard was done away with in 87' I think. Can I make myself one of ply n epoxy glass, my question, the weight factor, metal #165 +/- , is that weight needed ? Ballast? Added inside? I'm stuck, any thoughts, thanks ever so much, Mike