I spent 20 years in the agricultural and construction equipment industries. The rule of thumb was 5,000 hours on a sub-100 HP diesel engine is equivalent to 100,000 miles on an automobile. 1750 hours subsequently is equivalent to approximately 35,000 miles. This means the tractor you are looking at should have many good hours left in it. Of course, all depends on how the tractor was cared for. Just like cars, some with 35,000 miles on are in worse condition than some with twice the miles.
As with buying a used car, have a tractor mechanic/technician look at the tractor and give you a "professional" opinion.
OrangeGuy