Go to JoAnn's Fabrics or whatever your locale fabric store is and buy a SideWinder.
They are around $30.
If you have a 40% coupon from JoAnn's use that.
You can plug it in or use batteries to operate it.
If you plan to use these on a commercial machine I think you will find that you won't be able to provide a consistent enough wind on a hand wound bobbin. Your tension will be all over the place and you won't be able to sew consistently.
I would hunt down your competition and beg them to sell you a handful to get you through the weekend.
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