Dave:

WIthout a date of shipment, it is hard to determine exactly where the chip was used as the PO box listed (500) has locations ranging from Australia, to the Philippines, to Japan. However, it was probably used in Japan, in or around the Tokyo area by occupation forces stationed there after Word War II and/or during the Korean conflict when Japan was used both as a resupply point as well as for R&R purposes.

John