Finding ratings of older stepper motors

I've been looking at stepper motors at a local surplus store. My dilemma
is that although they list voltage/current ratings, I have no idea of
their oz-inch rating.

I've tried searching the manufacturers websites to no avail, and a
Google search turned up a lot of people asking the same question on
various websites, including eio.com's message board, but no answers.

So, any suggestions?

Here is what was on their labels. They are all 2 1/2" height, 3 3/8"
width and 3/8" shaft (0.375 inches).

Step Syn/Sanyo-Denki 103-820-2, 103-820-3, and 103-820-0241
2 degree/step, 4.5V, 1.4A 6 wire

Fuji Electric GPF3945-2B and GPF3945-2D
Same specs as the Step Syn above.

Thanks,
Steve