I have a feeling it might be Glenda, the looks and the fact the hat is hiding her hair, it could of been a snap decision by Alan Bell, he needed a female to walk with the chap, maybe one had been booked and could not make it.
Alan has done this when he used Marina as Mr Lucy's wife
Got to say, to me she looks a lot like Barbara Flynn the milk-lady from Open all Hours.
Also recently from After Paradise and also from another GREAT series with James Bolam, The Beiderbecke trilogy!