Need more info.
What oil are you running?
What RPM = what pressure?
How warm is the tractor?
Here is a guideline or "rule of thumb"
using 10w30 you should have
10-20 psi hot at idle and 15-30 psi cold at idle
20-30 psi hot at 1/2 throttle and 25-50psi cold at 1/2 throttle
30-40 psi hot at full rpm and 40-60 psi cold at full rpm
5w30 will reduce those numbers, 5w40 will be about the same and 15w40 will be higher. Winter time "cold" will make it higher too, just like summer time "hot" will make it lower.
From what you list, I would say you have excellent oil pressure. It will probably outlast you with proper maintenance. Remember change the oil, but MORE IMPORTANTLY keep the air filter clean clean clean clean. 95% of the wear comes from the contamination in the air.
jb