Six editions of "Show of the Week" survive from 1966:
SHOW OF THE WEEK:SHELLEY BERMAN................ 04/01/66 LLV5434R
SHOW OF THE WEEK:SHIRLEY BASSEY................ 22/02/66 LLV5435K
SHOW OF THE WEEK:THE DICKIE HENDERSON SHOW..... 01/03/66 LLV5436E
SHOW OF THE WEEK:THE SWINGIN' HERD 66:WOOD .... 15/03/66 LLV5437Y
SHOW OF THE WEEK:NINA AND FREDERIK............. 10/05/66 LLV5356K
SHOW OF THE WEEK:AN EVENING WITH ROLF HARRIS... 27/08/66 LLV5780A
"An Evening with Rolf Harris" is incomplete, about 9 minutes exists. All are film recordings.
As you say, the caption at the top of the picture and footage counter at the bottom show that this is taken from a BBC archive VHS...