Look into
www.mcmaster.com and look at their timing belt/pulleys, .2 pitch works, at least 1:2.5 reduction or higher, i.e. a 10 tooth on the motor shaft, and a 25 tooth on the driven shaft. I would go higher if you can find the pulley, say a 50 tooth pulley for a 1:5 ratio.
Chain and sprockets could also be used, or planetary gearboxes, if you can find them cheap enough.