550 is about the going price on these. I've seen them for $400 to $600, with $600 being new in the box and I didn't see any buyers for it.
They are great guns with a 1:20 twist rate instead of the stupid 1:38 twist.
Here is a link to a great article about the 444 Outfitter.
http://leverguns.com/articles/anderson/444Outfitter.htm
