Thanks for spotting the CA one, it would have escaped the searches I do since the seller mislabels it as a "Chevy Casa grande". It is also a '76, whatever it is.
Hard to tell if that one is a GMC since the ad doesn't show photos for the front or back, and it's missing its camper stripes. It does resemble Casa Grande #0719 that I last saw in Perris CA in 2008 which had black wheels and missing camper stripes, but the pics I saved were murky low res ones.
The $5 grand one in Washington state is likely Chalet #1102 which rotates in & out of Craigslist ads practically every other week. This version at Reachoo lasts longer:
http://www.reachoo.com/ads/193532221 It is the same one I mentioned
in this prior post, and I'm still having trouble prompting anyone into visiting the seller in person to get a copy (or take a good digital photo of) his factory blueprint for the camper.