As far as info goes it looks like an M111d, which was made in the very early 2000s. It accepted millennium style heads which could be swapped out if someone wanted to run a larger head on it. The one you have looks like the version that put out 225 lumens I believe and used m series bulbs.
Regarding price, a brand new x300u putting out 1000 lumens with an LED is about $230 give or take new. It does not have the ability to swap heads however.