Generator prices tend to vary with location and time of year, here on the Gulf coast prices are always higher during hurricane season, the more active the season and the more immediate the threat the higher the price. In the northern states it is much the same, but for winter, and not sure about the west though. There have been some artificial factors the last few years with California outlawing all older diesel generators a gross polluters, they did have a limited effect of flooding the market in the nearby states, but this supply seems to have dried up and I know I have read of a number of people searching for good older diesel generators in the Pacific northwest the last several months.
Having said that it is an MB-19, with a potentially overcomplicated esoteric control system, from what I know of the MB series they were built for the Air Force and were design to make it easy for aircraft mechanics to work on them using standard stock aircraft parts of the time. So it may draw less interest than something easier to maintain. I would say try CL and ebay, of course shipping is always a problem.
Ike