The modern repro bobbins will work on your machine, but you will have to guide the thread by hand as you wind the bobbin.
The modern repros are about 3/32" too short for the bobbin winder to fill the bobbin evenly from end to end - you usually end up with a "dog-bone" effect, with the ends being filled and the middle half full.
Guiding the thread onto the bobbin while you treadle isn't difficult though. Jenny at sew-classic carries them:
http://shop.sew-classic.com/Shuttle-...k-SCBN8228.htm
I've had the best luck finding vintage bobbins on eBay.