Looks like a good price. Seller has other parts for older jeeps, too.

“This trencher was removed from a 1950 Jeep CJ3A. When purchased was told it was in working condition. I have never done anything with it, but I applied a penetrating oil every 3-6 months on the chains, and apparatus. The link belt freely rotates. I have extra chain pieces, and the under Jeep components. Please call Denny for more information. I have collected Jeeps, and at my age I do not foresee doing anything more with them. I have other Jeep parts for older Jeeps. Asking $600 OBO.”

http://toledo.craigslist.org/tls/5865395773.html