Cut a couple strips of Neoprene to get the correct length & 2" wide strips, superglued together to make a belt.
Either a blender motor or hand held electric drill motor (both AC Induction (split-phase capacitor) motors) is probably best. Need to work out how to build a mount for whichever used. If possible, the base needs to be designed to switch the motor out.
The base has to be far enough from the top to hold the Neoprene belt as tight as possible, as long as the bottom doesn't break from the strain. It has to be stretched enough to be pulled from the inner edge of the PVC pipe and not have enough slack to attract itself and have the insides of the belt come in contact with eachother.