For something that you can actually buy, try this Ebay item:
226166478327
It is $7.69 + $3.00 shipping.
We don't need to analyze torque.? If it works, fine.? If it breaks, get something else.
On Ebay, an erector set motor is $12 - 30, depending on condition.
I see a benefit to the Erector motor.? If you are not using it, just pop off the belt.
But you need to create a pulley with something like a manual handwheel.
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