The “He” you referenced in the second paragraph is me (Russell King not NIW) that asked what seals the hydraulic pressure. In my experience I have seen many things that seal pressure with a ball bearing and a spring. Think about some pressure relief valves or quick disconnect couplers for example. Adjustment of spring pressure can be done with a threaded rod to control the opening pressure of the ball and its seat. So never having seen the hydraulic system diagram before for this tractor I am curious enough to ask questions and not assume that I know the correct answer.
In the last paragraph you wrote that my question about being able to use the tractor was advocating leaving it in a condition that is missing parts. My question was more about being able to move the tractor to a different location possibly from a muddy cold field to a nice warm workshop where it could be repaired properly. i was asking if it was possible not advocating anything as far as I read and understand what I wrote. I am sorry if it sounded any differently to you or others.