The image of the boy a the postbox with the signs for Udimore/Rye/Hastings interested me. The postbox is still there, and the sign is kind of still there, but now across the street. It's in Icklesham at the junction of Main Road and Broad Street.
Links below....
Image
Looking out of Broad Street towards the sign
https://goo.gl/maps/JXJpK
Looking in to Broad Street towards the post box (now green it appears)
https://goo.gl/maps/Noi2C