That's a 1967/1968 dual-standard (405 and 625 line) 25-inch Baird model M701. Not sure what they mean by the "Unused channel 14" - The Baird only goes up to channel 13 certainly.
(Perhaps it could reach the bottom end of "Channel 14" with the set switched to VHF channel 13.) From the angle of the VHF tuning knob, it does look as though the set in the film is switched to 405-lines VHF Channel 13, even though the set appears to be showing a 625-line colour picture (only broadcast on UHF).
It looks like the "Baird Colour" badge has been moved from the bottom of the set by someone. I've never seen one with the badge in that position before. Some models didn't have a cloth speaker grille either, and it looks like this is one of those sets.
[Edit]: Actually, the second picture looks like the set has
two "Baird Colour" badges on it.