Hi risuemav. What an interesting find. Are you sailors? If you end out not wanting to fix her up we’re sure you can find someone who will. You will have to contact a sail maker to get a cost. Do you have a loft nearby? The sail area for the Chaser Cat was listed at 165 sq ft. We’re guessing… and this IS a guess… the sail should cost under $1,500 or so new. You can always find used sails though.
All we have on the boat is here: https://sailboatdata.com/sailboat/chaser-cat
Good luck with this project.