Welcome. bkay was correct about that since it is not a 15-clone, it would be a class 15 Japanese machine. It may also have a JC number. I think I found the threading diagram at
http://www.sewusa.com/Threading_Diag...ng_diagram.htm
It looks there may have been two machines in that series and it looks like yours is a #1 and a manual can be found at
http://www.sewusa.com/Sewing_Machine...n_Manual_1.htm
That would take what is considered a 1 o'clock class 15 bobbin case and metal class 15 bobbins. I believe the part number for the case would be #JO1313ZW.
The link to Junebug29's machine
https://www.quiltingboard.com/member...47-622138.html
Unfortunately, the place I used to get my parts from is no longer in business. With the part number and knowing that it takes class 15 bobbins, you should be able to get what you need to be able to sew with your machine.
Janey - Neat people never make the exciting discoveries I do.
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