In the town of Notus, somewhere near Boise, ID, under the "heavy equipment" for sale section (wonder how many trucks folks miss by not thinkin' to look in there!)
http://boise.craigslist.org/hvo/5179569723.html
"1970 C50 tenwheeler"
"1970 chevy c50 Hendrickson walking beam susp, new 366 big block motor runs good, ps, will take a 20 foot bed"
$2900
(no area code listed, but easy to find) 695-5923