Typically, SE bulbs have a mogul base and are 175w, 250w, 400w, and 1000w.
Double Ended bulbs (HQI) are run in 150w, 250w, etc...
While searching for a bulb for you. I noticed that there were a few SE 150w bulbs for a 'medium' base MH bulb. However I could not find any of these bulbs in a color range that would be preferred for an aquarium.
Do you already have a ballast for a 150 SE MH bulb?