I consider the price "top of the line." It's in nice shape, comes with desirable attachements and is worth it to someone who doesn't have the time to fix on up. $800 is "just okay" but you could try getting it for less.
The tractor is nice for it's age. I would certainly try to get him down some. The rear pto on these tractors are somewhat rare. They are out there, and the owners usually know what they have and want more money because of it. If you don't need the rototiller, you can always sell it and the rear pto assembly to get your money back. Those pieces are desirable to the collector and gardener alike. Good luck whatever you decide.
If the tractor has hydraulic lift then it would definately be worth $800 especially if the fiberglass grill is in mint condition.But if it only has manual lift ...well I would say it's top dollar , and everything better be mint, and engine fresh, deck spindles,blades,rollers,propshaft and tiller should all be mint too. If it is , I'd give $800 for it in a heartbeat.