I would go to the Capri 14 home page and click on the Getting Started Guide. Toward the bottom of the article is a link to the Capri Parts List. I printed this out to have for future reference. Find what you need (rudder etc.)and call Catalina at 818.884.7700 for prices and to order.
There are a couple of links to sail shops on the home page as well (North Sails and Quantum sails plus one more that was the cheapest). For a set of racing sails (main and jib) they seem to run around $900-1000 new. If you are lucky, you can get used sails for about half of that, the trick is finding them. I think Catalina sells the recreational sails for much less than the racing sails cost. If you are not racing, I recommend a furling jib. I would'nt trade mine for anything.
Rigging you can get from Catalina or like SailNet.com or Layline.com or a local sail shop if you have one. Check out the rigging guide on NorthSail's and Quantum's web sight. I think it tells the exact thickness, length, and type of sheets to get for the main and jib. The original factory sheets are too thick.