I finally got around to rebuilding the slave cylinder. The replacement parts from the rebuild kit from Moss are the rubber end piece and the small plastic disc. I also ordered a new piston shaft and clevis pin. The picture shows the components of the slave cylinder.
The cylinder itself was quite dirty and took a good amount of elbow grease to get it clean on the inside and outside. The metal piston head was also pretty dirty. Reassembly is pretty easy. Spring first, then plastic piston end, metal piston head and then the rubber end piece. The end piece has two metal rings, one for the inside and one for the outside.
You can see that the end hole in the old piston shaft is elongated due to wear giving the clutch a sloppy feel (or lash as I think they call it). So I was glad to replace this part - BUT the Moss part was too wide for the end of the clutch fork. Fortunately, my neighbor has a grinding wheel and we were able to grind it to the right width.
Bleeding the clutch system is a little tiring, and really must be done with two people. You'll know when its not done because you won't be able to put the car in gear. Once it was done properly, the car shifts nicely and the clutch action is smooth and easy.