Yes, I know this light. It is the ultimate ARC collector light. It presently sits in my safe, safe from harm. The LS3 was the first 5 watter to hit the market two years ago and only about 30 were made. The light was driven at 2.5-3 watts. There was tremendous demand for this light when it was introduced. As far as I know, this light is still the smallest form factor 5 watt every made. The head has the standard LS form factor with a 2X123 battery tube with kroll. They sold for $200. About a year ago, I remember a LS3 go for $300+ on B/S/T.
Cheers.