first mh and hps are not interchangable so you need to find out which one you want then pick a ballast kit either hps or metal halide.
here is a hps http://www.1000bulbs.com/products.ph...ressure-Sodium
here is metal halide http://www.1000bulbs.com/products.ph...Halide-Ballast
im sure there is probably some cheaper places just dont know of any off hand and you should choose a multitap ballast kit, multi tap means you can wire it for different voltages standard house current is going to be 110 or 220 volt while there is other industrial voltages like the one you linked to a 480 volt ballast kit is going to be useless to you as you wont be able to use it.