Welcome to the board! You have a lovely machine, but it's really not rare. The Japanese manufacturers badged machines with hundreds of names on them. The reason that sometimes it can be hard to find any info about certain Japanese machines is because there are no records to search like there is for Singers and others.
What you have is an end loading zig zagger and you need this bobbin case-
http://shop.sew-classic.com/Bobbin-C...ger-JO1313.htm
You can buy new bobbins there too, but good quality 15 class bobbins are just about non existent now so I buy used ones from the big auction site.
Cari