I don't know what universe you are from but anything with a backhoe on it gas
or diesel with fetch 4 to 5k just about anywhere. Some of the late 60's and
early 70's International backhoes have brought upwards of 10k on ebay (must be
collectors). I have a 3414 IH and while a good tractor they are fairly slow to
operate. I mainly use it for picking up heavy stuff around the house and shop.
As far as your 580C I would run. First off it can't be a 1979 and still be
gas as I sure don't remember that even being an option in 79. More than likely
it is a 1960's 580 CK which predates even the B models. They rarely had cabs
and gas engines were the predominate engine option although there were some
diesels. The hour meter is obviously broken. One thing about the early Case
backhoes they are built more like a converted farm tractor where as starting
with the 580C series there is a short driveshaft that connects the engine with
the transmission that allows you to take the trans out without spliting the
whole tractor. To me ease of maintainance is a big factor in anything I look
at.

tim