This forum does some things well particularly related to cruising and cruising boats, but others, not so. Here are a couple places you can get better info on a J24 than you're likely to find here:
U.S. J/24 Class
Most sailmakers and hardware manufactures can give you very specific cost/parts information for anything related to the J24. If you want to save $$$, it's up to you and the magic of ebay and the like.