Above: just "She Loves You" from a superior copy of the film. "The Mersey Sound" was a BBC television documentary that features the Liverpool sound by focusing on The Beatles & 2 unknown bands, The Undertakers & Group One.
The Mersey Beat was first broadcast on Lennon's 23rd birthday, 9 October 1963, from 10.10-10.40pm, in the London and northern England regions. Its first nationwide broadcast took place on 13 November from 7.10pm.
The above is a 14:59 edit which ends abruptly, below is a playlist in two parts of a 29:16 version of the film.
Above is a 1964 colour Pathe Newsfilm with a similar name: "The Mersey Sound", but also known as "Liverpool - Home Of The Mersey Sound" to distinguish it from the earlier title.