Yep. Tires are more expensive than that.
Also, consider that only a PORTION of that $810 was the actual parts to repair. The Majority was the Service-Call plus the Labor.
A new tire under the same circumstances would likely include Service-All labor in addition to the tire. (and purchasing only ONE new tire would likely be a mis-match to the other 3 on that 4WD tractor…. possibly placing a strain on the driveline under some circumstances. By repairing the existing tire those addt’l problems do not present themselves.
(In a somewhat related matter…. I found TWO Mounted New Tires on N.O.S. front wheels for my tractor priced at $500 for both. It was SO Tempting!
Until I realized they’d be replacing existing 30-yr old tires…which would then slightly mis-match the rolling-effort of my 30-yr old Rear Tires…. and chances are, the existing tires will loong-outlast ME anyway. ( They have about 60 % tread remaining and I’m in my late 70’s ….. using my tractor on grass about 30-hrs per year.).