Matsu Moku Kogyo = MMK
"Some models of Epiphone, Vantage, Aria and Washburn branded guitars (pricing from middle class to high-end) were manufactured by Matsumoku Kogyo. Their sales were weak and they tried to manufacture other wooden products such as Buddhist altar, wardrobe and domestic sewing machine. Eventually this company went bankrupt in Feb. 1987. Some of the employees of Matsumoku Kogyo were hired by other guitar companies in this area. Most of them are retired, so it is very difficult to gather information. MMK means Matsu Moku Kogyo. They didn't manufacture pickups themselves. They purchased pickups from Keiyo, Goto, Nisshin Onpa, etc.
Some of the employees from Keiyo, Goto and other failed companies established a company called Kariya and they still manufacture and sell pickups. However, they cannot manufacture 70 and 80's vintage pickups. They don't have the mold any longer. (The mold got old and probably it was thrown away.) Considering Matsumoku Kogyo was bankrupt and other pickup companies were also bankrupt, we don't think there is any stock item at factory.
Failure rate of disconnecting problem with coil in 70 and 80's pickups seems to be high. We have heard that someone rewinds coil in business."
RaleMan