Do these have to be well-known shops that used to be "household names" or can they be independent shops which went to the wall years ago?
Household name: Wimbush's Bakeries in Birmingham - I lived in Brum for a while in the 1960s and was addicted to their pineapple tartlets: a sweet pastry case, a layer of pineapple jam, a mound of synthetic over-sweetened "cream" and a coating of yellow icing dusted with green vermicelli - the four essential food types!
Small local shop: Old Snowball's paper shop/tobacconist, - specifically the sweets counter: sweet cigarettes, gob stoppers, sherbet dabs, penny chews, parma violets ... and big jars of blackjacks, acid drops, barley sugars, hundreds & thousands, etc, transferred with a scoop into a tiny paper bag.