Yep, you can rebuild them, but hang onto your check book when you price the kits, if you think Agco thinks the valve itself is worth gold. Had to rebuild all the valves on the 1254 last year. Right now, knock on wood, I think the thing is going down the road. If I absolutely had to keep it, and was going to do this project again, I'd throw all that air junk away, and figure out how to get regular TeeJet electrics put on it.

As far as an aftermarket source for a complete valve, you can try dultmeier.com