You need more than one wall between your bed and the tumbler if you want to get any sleep. Do not forget about your neighbors either. If you do not have a secluded room or basement, consider making a container for it. A cardboard box lined with Styrofoam, or covered with an old blanket, will reduce the sound considerably. There are two kinds of tumblers, rotary and vibratory.
Rotary tumblers are the ones most people are familiar with.
They can be found at any rock shop, scientific supply houses, and many stores that sell toys. They are the least expensive and come in the widest range of sizes. Vibratory tumblers shake the ingredients, rather than rolling them over each other. They have the single advantage of being faster. What would take weeks in a rotary tumbler can be done in a couple of days in a vibratory.