Being a former Marine I couldn't resist this especially since I collect Japanese art. It's an art form of gold and silver inlay over a controlled rusted surface called Komai. Has the name Mac on one end and Jeauue on the other. I'm told a unit flew this style helicopter out of Okinawa in the 1950's and 1960's. Other than that suggestion I have no idea when it was made. It has the Amita logo on the bottom. Do the characters under the names look like kanji?
Thanks for any help,
Howard Dennis