Well, here's some info on these beauties.
The gold 65s were given to dealers to use as they saw fit. They often used them as "prizes'.Such as: bring in your oldest cleaner.. get a new gold Convertible... an enticement. But, they were never meant to be SOLD, but, given, to celebrate Hoover's 50th anniversary. They only made about 5,000 a quarter. So, 20,000They were built in late 1957 and 1958.
As far as the "flower power" model 728, they made 121,500 built from 1971 to 1973.Shades of taupe and Camellia. Although splendid cleaners (a B line) they are not that rare.
I hope this accurate info (directly of of North Canton) books, helps everyone.
John