There is one more in Kasauli itself in the Market called Aarhat Bazaar..
As far as i know there are other old boxes in Calcutta (5), Darjeeling (2) and Shimla (1).
See the link
https://www.facebook.com/KasauliTheBeautifulPlace/posts/889470634512087For interest, this splendid pillar box stands just inside the Kasauli Club grounds. If anyone is aware of another like it in India , I would be very pleased to know. They were made by Suttie & Co. in Greenock, Scotland in about 1856 and a handful still remain in use in India.
Toby.