As some of you may know, I had my first successful "build" after having completed my Graflex Luke ANH saber. I'd like to build a Vader ANH saber, and know I'll need an "Emitter" shroud for my Heiland battery tube (which I don't yet have). The question: what kind of tube, exactly, do I need to buy, in order to serve as the basis for the build? Thanks in advance ... I'm sure this information is available just about everywhere, but trust you guys to give me the best, most accurate info!