I bought a 2000 16V Espace via eBay
with the clutch hydrauics slave pushrod end broken. As described above it is quite possible to repair this.
Took me three hours in the street with some hand tools. The slave piston had popped out when the pedal went to the floor, so some fluid had leaked out from the lower section as well.
I removed the slave cylinder (2 bolts with a 13mm spanner) and raised it above the join. Then I pulled the pedal back into place so it sucked some fluid back in, and I guessed/hoped that the air wouldn't get beyond the join. Then I disconnected the join in the pipe. I used a spanner to push the ring back to get enough area to push on, but it comes apart easily and self seals each side so doesn't leak. Back in the car I was pleased to find a hard pedal to confirm that there was no air in the top part of the system and that I wouldn't have to take out the dash.
Then I sawed the head off a 10mm bolt to the same length as the pushrod and the broken plastic end, and filed the ends to be rounded and smooth. The rubber boot stretched over this easily to keep the dirt out.
I flushed out the slave cylinder with new fluid and filled it to the brim before starting to put the piston back in. The connector won't let the fluid out, unless the sealing ring inside is pushed back, and I found that a small 1/4" socket of around 10mm fitted nicely in the hole so I could push gently with my thumb to open the seal while pushing the piston into place until it was part way in and just meeting the spring inside. No air bubbles and ready to go.
The pushrod presses on a lever on this box, and the lever pulls on a short cable that hooks onto the clutch operating lever. I unhooked the cable so I could put the slave back into place with the two bolts just started. I then reconnected the hydraulics, and pulled the cable to hook it back into place. Then just had to do up the two bolts to get it all to fit properly.
I'm not sure whether I was lucky or whether it's designed that way, but no excess fluid came out of the top end, and since I didn't look up there I don't know whether this one has a reservoir or not.
Anyway, the clutch works fine, and all that for the cost of a 10mm bolt I had in my toolbpx anyway.