Your stamp is the local printing 1941-1955 issue of the Sri Pashupati issue of Nepal ,it is the 2 pice value which is the lowest value of a set of 7 .the reason they were produced in Nepal was because of the war.
There is quite strong evidence that shows they were printed for favor for the philatelic dealers in Kathmandu .There are four different watermarks found on this issue and it was printed on Luxor Bond paper,the paper was made in Canada . Two different machines were used to perforate these stamps, the "A"machine was used for the verticle holes , the "B"machine was used for the horizontal holes .
Your 2 pice stamp was half the normal letter rate being 4 pice, the highest number of stamps printed was your 2 pice. The shades of this stamp run from very deep brown ,pale brown,dark brown ,deep to pale green and to deep chocolate.