You could always buy just the drill type motor and make a gearbox.

thats what I did.

Glen, sounds like your gears werent correctly meshed. They tear up real quick if even 1mm out.

If anyone gets sick and tired of drills, let me know on info@jamesbaker.f9.co.uk and Ill tell you how much my custom made gearboxes cost. They are not as cheap as drills can be, but they are supplied with motors and ready to bolt in. Choice of ratios and module. I can even do a double trouble gearbox which uses 2 motors to turn 1 output shaft. Quite neat.