About the least inexpensive way to power a bead roller effectively would be to use a HF 1/2" low speed high torque variable speed reversible drill and a flex plate from a small block Chevy or brand of your choosing.. get the gear from the starter and the ratio will be about right..I used a 110 tooth gear and a 13 tooth gear on the drill motor and a 35 roller chain but the big gear is a bit pricey.. a flex plate would be about the same ratio and much cheaper.. you want it to be reversible and variable speed for intricate work.. good luck with all your endeavors! From an ex Iowan...
I think you want a low speed high tourqe motor, something with a gearbox attached to it. Lots of amp draw, I think anything battery powered wouldn’t last long. Butt yeah grab a bowl of weedies and give it a try.