NEMA 23 holding torque guess

Hello:

I have about 50-60 Sanyo-Denki NEMA 23 steppers, 6 wire 3.5 V 1.5 A per
phase. Sanyo-Denki part number is 103G770-1848.

I will probably keep a dozen for a weird project, and want to sell the rest.

They are spares for dot matrix printers...I assume removed from new
equipment, but I don't see any signs they were installed. I bought them all
in one box, packed like sardines, so the labels are a bit scratched.

Anyone have a way to guess at the holding torque, or have data on similar
series? S-D was uncooperative, saying they were designed for a customer and
thus propietary.

I was going to guess 60 oz-in just based on similar average NEMA 23
single-stack motors.

Thanks

Murray