Kalamazoo is still in business and had any of the parts I needed, not cheap though.
I have bought and refurbished a few horizontal saws. There aren't many parts and all the bearings and seals are off the shelf.
If you have a lathe and mill many more items can be made.
What it is worth would really require a much closer evaluation than an ad.
If the castings and gears are in good shape replacing all the bearings and seals doesn't cost much finding them on ebay, the local bearing place will be much higher.
^ $400-600 saw.
If any of parts that need replacing from the factory only, priced far less to scrap value.
On the other hand he could sell a few parts off it and easily pocket $400.
A good running saw of that size with a good going through, with a 1 phase mtr can fetch $1500-2000.
Complete sandblasting and painting, more.