The Sea Scouts shown in the film, are wearing Cub Scout caps.
As Florence leaves the bank toward the end of the movie, the bank's name is seen on the entrance door: "United Bank Inc". This is supposed to be a British bank, which would, in 1959, be named "United Bank Ltd".
Inside the bookshop, modern Penguin Clothbound Classics can be seen on the shelves. These editions were put out in the last 20 years, bound to look like older styles, but are, indeed, recent publications.
A book purporting to be Philip Larkin's Collected Poems appears several times in this film. However, Larkin's poetry was not brought together in a single volume until 1988, 29 years after this film was set.
Modern plastic uPVC windows visible in background of certain 'town' shots, and modern PVC wellies worn by 'fisherman', small but noticeable details.