I remember it well. It was on a LP but I think the title was something like "Best of Sellars" but I can't remember for sure. The cover was a picture of the lower part of a man who had been hanged from the branch of a tree IIRC. The speech was a wonderful take off of Harold MacMillan who was prime minister at the time. It was full of typical politicians platitudes which sounded good but meant absolutely nothing.

It had a number of other very clever sketches on including the Irish traditional band who all ended up fighting each other, the "Holiday" type program based on Balham in S. London with the local craftsman who made holes to put in toothbrush handles.

The album dates from the early 1960's as I first heard it in a friend's house in 1963.