The masthead is the same as a J/24, except there are two. Good luck changing the inner one with the mast up, I had trouble with it with the mast down. It has to come up from the bottom, and the masthead is pretty small. I thought I bought mine from http://www.apsltd.com/J24-Sparcraft-Welded-in-Masthead-Parts.html but the sheave I got was aluminum. For the jib halyard box, I was able to move around unused sheaves, so I only had to replace a couple. On the older box in order to replace those you have to pull the box out and find someone who can rivet new ones in.