This is a piece of stationery from Burma during the Japanese Occupation. 

This envelope is a King George VI 9 P.S Green with a Truncated X in Blue.  It also has a Japanese Officer's Seal in Black, as well as a 3C SURCHARGE.  This is VERY RARE

This item is over $100 USD so I will ship it using Priority Mail in the US, and registered mail overseas.  This is to ensure that it reaches you in a safe and timely manner.