Manchukuo - 1937 5Y Manchukuo money order stamp seems to have been put to some alternative use. The cancel which reads International Exchange Department seems to be dated 4th March 1937, but it is possible a "3" is missing. I suspect that it was supposed to read 4.3.34, which would make more sense as the stamps fell out of use in 1934.The date-stamp, not standard post office issue, was for international use (perhaps to China).