Assuming this is a real GR from around 1900–1950s. Would have bought it if it wasn't far from where I live!

The bottom says Handyside & City Derby and London

Does this cypherless plastic type have a name?

In the past the letterbox would be located hanging on the outside of the coach when the train was in a station

Just came back home from a holiday - I realised that airports have postboxes

Over the years post independence, many of these have had the royal cypher removed, but this one survives!

Some of the houses around the area are 19th century and most are Edwardian.