I have a '98 I am fixing to put back on the road. It has 110K on it. A tree fell on it. I would say, your prices on parts are Ok overall. I'd say to low on the seat, and you could get a windshield for less. I bought one for $75. I installed myself.
I would say that in excellent condition and low milage, these can bring $3000 to $4000. Your milage hurts you. I think it would be hard to peg the different types of buyers for this kind of vehicle. The 4 Wheelers would have a different take than someone after a Daily Driver.
You might call around junk yards for used tires. There is one around me that sells a set of four for $100. Sometimes in very good shape. Also, if you have a pick-n-pull by you. Try:
http://car-part.com/
Tom