Probably a bit above scrap value Gregg only because without it proven to be running, it's basically a parts machine even though it's intact. If you can get it running, that should improve the price. It may cost very little to do - such as new spark plugs, replace oil in pony, drain any condensation from the main engine oil pan, replace mag condensor and clean-up points, etc.

If it starts relatively easy and the blade works ok, I would guess 3-4k? I haven't bought a D4 but I've seen prices around that mark, some higher, some lower. It's probably worth your while to invest say 8 hours in getting it going because as well as getting a better price, it will sell more easily (getting 10k is awesome but only if you make the sale and get the $) and also loading it out. If it was "running when parked" : ), then most likely it's some basic items that need attention: spark plugs, plug wires, condensor, points, carb, and then bleeding the diesel system if it's drained back. Getting the pony running and being able to turn the main engine over with it will get you a long way towards success. The pony is a very simple engine so they're very easy to get going so long as they're not actually damaged. One key thing to do with the pony is to drain the oil, and refill it with new. They only take a quart but it's a precious quart - if diluted with fuel, the pony risks throwing a rod, so a quart is very cheap insurance.
Hopefully someone within reach of Avery CA can come help at least assess the likelihood of getting it going. There are a lot of members within a couple of hours of your location - maybe one of them can come out for a Saturday rescue mission!