So the curly letters under the crown show which monarch was on the throne when the post box was installed, most usually have ER (Elizabeth Reigns) on top of each other with II (Elizabeth II) in the bottom part of the curly E; although some will have GR (George Reigns) with VI in the bottom of the G or just VR (Victoria Reigns) as they are still around from when those monarchs were on the throne. So ER with a VII in the E which is what I'm seeing here just doesn't make sense.
*wubbalubbadubdub*
*chink of mail falling*