New hope:
Benny Hill was shown here in Canada and I loved that show although it became too repetitive and predictable. Monte Python was also regularly broadcast as was "On The Buses".
I recall that "Steptoe and Son" was remade in the US as "Sanford and Son".
Some of the other shows you list may also have been Americanised and retitled. Although not fitting the 60s or 70s criteria, a US version of "Whose Line Is It Anyway?" was made but I've also seen a version from the UK but I don't know where the show originated.
Looking at the names you list, I suspect "H. R. Puff 'N Stuff" was probably a remake of the puff name you mention.