That number is the model number. 679. the last four may be for options.
A picture would help - my white that is has a similar type model number - takes class 15 bobbins. Many of the post WW2 whites take that bobbin. Pre WW2 machines take something totally different.
If your machine takes the older style, it's almost certain to also take top clamp feet. If they are side clamp (like modern machines) then it's a "newer" machine and you should be able to buy bobbins that will fit at Wallmart.
This is a machine that takes the older style bobbins,
this is what the bobbin and case look like.
This two Whites take the class 15 bobbins. the green one is model 670, or something like that. But it's tag also has the same as you describe
this is model 967
