Being seen in Scotland it is very plausible that it was an early Baird field sequential color set. The British electronics co. Pye used a field sequential system to telecast an experimental color broadcast of the coronation of Queen Elizabeth in 1953. Doubt the set seen in Scotland was one of the two 1953 color sets which used a crt to display the field sequential image. But who knows? Here is a link to more info on this system:
http://www.earlytelevision.org/briti...erimental.html
-Steve D.