After building a TV stand and computer desk out of aluminum extrusion, and a few other miscellaneous furniture things, now and then I've been thinking about making a case, too. Never really got past the thought; my PC-O5SX is suiting me fine. Good to see someone else running with the idea though.
Old thread but I get my extruded aluminum from 80/20. You can get black anodized but it is about triple the cost of the bare stuff. I built an entertainment rack for my receiver, amps ( 100+ pounds each ), and A/V gear in black anodized and that cost over $800.