What brand of ballast is it and where did you get it from? You may be able to contact the manufacturer and see if they seel the enclosures seperately or not. If not, you will just have to find an electrical enclosure and make it work. Home Depot and Lowes sell some larger junction boxes both in metal and in plastic. I used a 12in. by 12in. junction box to house my two 400watt ballasts. Drilled a few holes and used grommets/strain reliefs for the cables coming in and out of the box.