IceCap 250watt Halide Retro Kit - NO BULB: Premium Aquatics
Just like this but it doesnt have to be this brand it was just the fastest one I could get to. Lots of companies make these so just look around and yes e-bay might be a good place to get one of these. Make sure that when you are looking at what is included to find out whether or not a bulb is included or not. IMO it is better to get one with no bulb that way you can get the exact bulb you want color wise.