It is currently not available other than the broker, which means someone had one from a while back. They are going to likely add it to a House of Legends vendor in the near future.
what Seth said. I should imagine it'll be one of the things that end up on the base item vendor they're adding soon ( er or later ) in the new Living Quarters in the HOL.
Are they not dropping from end game instances anymore? I could have sworn I got either a Mammoth or Pterosaur Display just a week ago from one of my Large Doom bounty boxes, either that or the elite duo. I could be wrong though since I tend to carry a copious/unhealthy amount of furniture on me. Either way, like others have said, hopefully it'll be much easier once the base item vendor arrives. However, I would continue to check on the broker since I'm sure they're still in rotation in some way or another- I just bought one on the US PS/PC server last night for under a mil for the base I'm working on.
I just got one sabertooth tiger display recently, too bad i put it in my base already. :/ Dont know where i got it tho. But have few stuffed historical animals, so they drop somewhere for sure.
I can also confirm that these base items will randomly drop though there could be content that has a better chance for it to. As an example, when I run the Test Subject # 1 solo instance, a lot of the base items that drop off the first lootable boss tend to be occult, shabby, and playhouse items though playhouse seems a bit more rare. Otherwise it does seem to be RNG at times.
I think they drop now in EEG content. I've gotten all 3 recently. They are pretty much worthless on the broker now too. So I'd just run EEG content.
Not raid, it refers to the clamp content. I am pretty sure I got mine out of the bounty loot boxes, but it could be in various places as well. Sorry, I don't think there really is an exact farmable area.