bingo!cave dave said:If you didn't already know this, there might be a spare bulb locatated in the clip that holds the wire to the band.
Looks like you got a good deal, the replacement bulb will cost more than the light. Spare bulbs available through IMO.
http://www.caves.org/imo/frames1.htm
click on bulbs on left frame then scroll all the way to the bottom. The Xenon is brighter than the standard but runs for less time. The xenon bulb has a white base.