The Iris was discontinued last year.
3DR made everything open source including 3D print files.
This is just retailers purging the last of inventory
That is a pretty good price.
Keep in mind it will be a DIY if you get it.
I would buy one if I just needed another test platfrom.
It runs on ardupilot so it will have support for a long time.
The pixhawk 1 Flight Controller and parts are its true value