I agree with what most have written here, especially Cathy. But I suspect the parts were taken to be sold. For instance, quilters are a trustworthy bunch, in general, but many are warned to take the bobbin case of a Featherweight when going to lunch at a retreat or class or it will vanish.
If you have trouble with the machine after getting the machine cleaned, tri-flowed, and the parts installed, then I think it is the new bobbins. Singer 221s can be quite fussy about their bobbins. You might need originals.