MF50 stabiliser ram leakdown

One will not stay up for more than a few minutes, other is overnight drop.
According to the repair manual there's a ball & seat in the valve assy on the ram.

I can't find a repair kit & nothing more than o-rings listed in the parts book or on the AGCO site. pics from repair manual and red lines to what I'm thinking should be replaced, the balls and the seats.

Nothing in the parts book shows these pieces, just a couple O-rings.

Do I have to buy the whole 1605965M92 VALVE to fix this?...

MF50 stabiliser ram leakdown