I'm not sure where it is at, since I haven't seen the tractor yet in person, just in pictures.  

I'm torn because the tractor was restored about 8-10 years ago, so its in nice shape with good paint. The owner said the tractor has sat for about 3 years or so as well. He said that he was using it and it just up and quit. Wouldn't start, so he checked the oil and he found antifreeze in the oil. So the crack is definitely in a bad spot. He is selling it for parts, but it just looks like its in too nice of shape for parts at this point. I'm going to try and look at it this weekend, since it is not located locally for me.

I've been looking for replacement heads for this tractor, but they're not very easy to find.  I'll have to see what else I can dig up this week, and see if there are any parts tractors at some scrapyards.