Yes, they are NEMA17 (42mm. square). The ones I have are probably a custom OEM version - they are bipolar (4 leads) with a winding resistance of 9.8 measured Ohms per phase.

I guess you just won 4 of these motors just for describing your project. If you would PM your UPS account number (and shipping address), I will get them out to you. Total weight is 3lb.