It's from Taiwan the Chinese reads as follows: on bottom 中華民國郵政 (the republic of china's postal service) top part 節約建國 building the economy/country (as you can see by the photo there are trains/boats/factories) this site has a stamp that looks like yours The date would make it 1942. However I would check to see if it's an original or a reprint. Hope this helps. Also for future reference this site shows you the date conversions for the years western/ japan /taiwan.