Small jib
I have sailed my Oday 23 in winds of 25+ knots with a reefed main and 100% jib. The rail was almost in the water, but she held up. I don't think I would want to be out there in any kind of wind that requires a real storm jib. Assuming however that you do (and are willing to go on the foredeck to change sails in that weather), you can find the manufacturer's sail dimensions for the 23 on this site. Go to the Resources tab on the home page, then manuals and documentation. Any sailmaker can take these measurements and make a storm jib for you. I would guess that real storm jibs for boats this small are rare so that used sails may not be available; the boats were not designed for heavy weather and I would be surprised if a lot of owners have gone to the expensive of having heavy weather sails made. You could just use a jib from a smaller boat, but that wouldn't be storm jib. Storm jibs are made from heavy cloth, have reinforced stitching, and fly "higher" than regular jibs. Good luck!
