It's done that way because doing this way means you will always have power steering regardless if your using the loader, 3 pt or anything else. Basically makes a dedicated hydraulic system to the steering, only sharing the fluid. Some tractors also use it for the PTO clutch pack.
You may not have a cylinder for the cylinder. It may be done at the steering box. Not familiar with the model and very little info online, so can't really help you much.
I know the area more or less as I really enjoy that part of the country by I'm not familiar with hydraulic shops in particular. I'm sure there are a lot of tractor dealers though. I'm located more in the center and towards the coast, around Leiria.