The Maricat is a great little boat, hundreds being sailed at clubs all across Australia. It's still being produced with sail no's well into 3300. Parts are readily available. Check out these webpages http://www.isq.com.au/nacra/BRISCAT/Maricat.htm
http://www.catsailor.isq.com.au/index.htm

It can be tweaked very simply, similar to the Hobie 14 on which it was modelled. I think its a better boat than a H14, more comfotable , and less inclined to pitchpole.
The Tips in Rick's book are very applicable to this cat as well.

Lay the Mast back using a pumb bob from the halyard, it should hang vertically over the rear beam or at a minimum the rear of the tramp. You may need to extend the forstays using forks to do this. Kick the rudders under about 50mm
Once you've done this, then work on you sail[s]to ensure that that their level.

Then go sailing.