Brian,
I believe all of the 1500 tillers were 2 point. If they are, you will have to do some major modifications to get them to fit anything else. If they happen to be three point, they should just hook right up.
There are a lot of different prices out there for tillers. A lot of it depends on the type of service done to them before they are sold. If they are just cleaned up a little they will usually be a lot less ($250) than the ones that are completely taken apart and rebuilt ($700+). The tines also add a lot of extra cost to the tiller. If you are going to use it a lot you need to look for tillers with good tines or count on spending $5-$10 per tine for new ones. Some tillers even have hard faced tines ( a good option if you use it a lot). Around here you can usually find a good non restored tiller for about $200- $275. Better tines and hard facing adds about $100. I have, however, seen rebuilt tillers sell for around $900. I guess it depends a lot on your location.
