I've seen a few selling at 3 keys so thats why I've include it on the range, still some sell a lot more don't (aka you would get insta added if you were buying them at 3 keys) here are some unsold examples:

http://www.tf2outpost.com/trade/5672751

http://www.tf2outpost.com/trade/5780134

http://www.tf2outpost.com/trade/5758477

http://www.tf2outpost.com/trade/5746160

http://www.tf2outpost.com/trade/5786864

http://www.tf2outpost.com/trade/5786864

http://www.tf2outpost.com/trade/5785604

EDIT: I've just took a look at the clean unique version in case it needed a change too, and it seems there are very few clean uniques while people are uncrating haunted items like crazy on their search for halloween unusuals, so oddly enough haunteds are cheaper than uniques, weird