What are the speakers you very rarely find in the Used market(Audiogon or Anywhere)?

I'm looking for Vandersteen Quatro CT, Wilson Sabrina or DeVore Fidelity Orangutan 0/93 or 0/96. I rarely find it or in some cases, before I make an offer, it is gone. What other speakers are a rare find?
MBL 101 radiostrahers, one of favorite in the world 
and big Marten Coltrains.
Went out of business many years ago but John’s speakers were way ahead of their time and in some ways remain SOTA. John recently passed away and I count it a privilege to have known him back when he was designing and manufacturing loudspeakers.

Any Magico model! Especially considering how many are sold in the USA, it is very rare to find them used.
Here's a beaute...I have NEVER seen a single used pair of T+A's amazing electrostatic hybrids, The Solitaires, for sale!