Need a little more information on this... dust seals only control dust, not oil. From the parts diagram, it looks like hydrostatic steering which means it doesn't have a steering box. It has what is called a pump, and a steering cylinder. Cylinder is a cylinder... parts look available. Pump service parts look limited, but seals are available. You definitely need to track down a WSM for this one as it looks complicated.
Just happened to see this thread, yes I know it was originally posted about 8 months ago!
I think the OP was talking about steering controller ( J10500 Steering Hydraulic Pump, as Kubota calls it), which is a pretty sophisticated hydraulic steering controller.
My 1996 F3060 has Eaton Orbitrol steering control unit, made by Sumitomo under a license agreement.
Kubota is not selling these Orbitrol parts for my mower anymore, at least that's what I was recently told by a major dealer saying that "Oil seal K3511-38140" is no longer available individually!
Not sure if the whole $90 seal kit K3511-38390 still is available or not?
Complete Eaton seal kits can be found on the eBay with this Model No. RU051A080F1A SK923 (at least that's the model on my F3060).
It's a US vendor based in the Midwest and was very helpful and apparently able to rebuild these units if needed.
I just recently replaced only the "Dust Seal" from their Eaton kit due to hardened up leaky old seal.
Left all other O-seals etc. as is since they looked OK.
