I plan on manipulating the inside of the vacuum with layers of gloves bolted and sealed to the walls of the chamber. I'm already going over all of the structural aspects on another forum.
Currently I am only using pure cesium as a reference point as to how potent of a vacuum I need to safely store it. I would never need a vacuum more pure than what is necessary to keep cesium from reacting. However I do plan on isolating cesium eventually, most likely via electrolysis of molten CsCl.
As for the vacuum pump, I do not know. My dad owns one that I could use, but it is quite old and possibly broken (he lent it to a friend who may have accidentally broke it). That is the reason I came here, is to determine how powerful a pump I would need to suck sufficient air out of a 1 cubic foot box to keep cesium from reacting. I don't mind a little tarnish, I just don't want the stuff to explode, spontaneously combust, or be instantly contaminated.