An Invoice for goods purchased at a period 1939/1940

"My parents who farmed a 50 acre holding at the start of world war 2 would do most of their shopping in the local shop (long gone). I think the system was , if you had cash you probably paid the full amount , if short you put the balance on the "book". The currency at the time was 240p to the pound. It's interesting to see the range of items available & the prices of some. E.g. chocolate 1p, Pair of sandals 4 shillings I notice Sloans Liniment is still available."