I need the serial number off the ID plate on the dash.
Pump squeal is not unusual. Before he condemns the pump, he should crawl underneath and chase the two steel lines that go to the rear PTO valve. Look to see if they are touching one another or touching the tractor.
If so, then get some short lengths of heater hose and slit them lengthwise. Slide these short lengths over the steel lines and position them where the lines are contacting other parts. Zip Tie them tightly into place and then Zip to the line to something solid.
In order to determine if the pump is actually bad, he needs a 5000 PSI glycerin filled pressure gauge along with some high pressure hose and fittings. No point tossing a good pump if all that's wrong is pump noise being amplified.