John Deere 4600 steering valve

[IHLoadstar1600]

I've got a JD 4600 compact utility tractor at a golf course, the steering valve (directly below the steering wheel) is leaking pretty good from the top where the shaft comes out. Can anybody give me some leads on finding a seal kit for the valve or something, John Deere doesn't offer parts for it, just a replacement (not going to spend $775 on it).
Tried to contact Sauer-Danfoss but that hasn't worked yet.
Any help would be greatly appreciated, thanks.