Thai or Cambodian. Good old example. 7” forged iron blade decorated with eyebrow marks on one side. Secured to the wood haft with two rivets and a copper ferrule. The haft tapered through its 14 ¼” length. One side impressed with a wave motif flanked by inscriptions. The blade with old stable surface encrustation. The haft with expected abrasions and dark patina. Fighting sickles evolved from farm implements usually where the ownership of weapons was forbidden for the peasant classes. That history, in Japan, goes back to the 15th century. This example is from the 18th-19th century and fully developed as a weapon. Its form is that of the Japanese Kama, specifically associated with the ninja who were subversive mercenaries skilled at sabotage, and assassination.