It is still lootable, or at least it should be. It's given out as part of "generic rare drops" through Dhaal encounters.
By default there is a 2% chance per encounter in the relevant locations to trigger rare drops. However, there are many (usually 4-5) items that are considered rare drops, and you will only get one of them randomly each time the main give-a-rare-drop layer triggers.
This is further complicated by a few special holiday item drops also work their way into the loot system just before the "pick one rare item" part. Worst case, you could end up with 14 potential items in that list, although most of them are removed from the list of potentials if you already have one.