I already have a SEWMASTER, but I think it's a company name rather than a model of machine? Yours look to be rather old toy SEWMASTER models from the "KAY AN EE" company (you can't see that from the label but google "KAY SEWMASTER" and it's everywhere) which seems to me quite likely unrelated to a modern bobbin of thread. So that's a hit.

And Ocean Master, well I definitely don't have that, so that's a hit as well.

I can't believe they actually wrote "IMITATION CRABMEAT" quite so large.

Cheers!

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