Pipe wrenches and hammers work as well, at least for getting frustrations out.
I have not had a lot of luck with rebuilding the cylinders, 1 good, three bad.
If Moss will warranty the unit, I would go that way, if not, it might be worth looking into a replacement.
I checked my catalog, and I found the Beck-Arnley number in case you want to try to find it local.
Clutch Slave Cyl Assy - 072-4260