The link for the one in post #3 expired, but I kept the contact info for it. I've discovered some of these remain unsold for a year or more by the same seller.
Latest one in
Denver CO, seller is open for reasonable offers, said the previous owner provided all the emissions records, which it passed even just recently. Serial #1009, built 1/77
As ever, no affiliation, the only thing I ever ask for is the serial number / build date from the sellers, and that they try to make sure these go to a really appreciative home.