What used speakers raraely come up for sale

Lets keep it under $7,000 used, but interested to hear what used speakers rarely get listed for sale because they are so sought after and if they do appear they get snapped up very quickly?  Cheers
Sonus Faber Extremas (monster two-way), Dali Epicon 8s (have never seen used), Cain&Cain Ben Single horn, Dunlavy SC-Vs.
Extemas used to come up fairly regularly years ago, but no more. Early in the thread, someone mentioned Diapason Adamantes. There was a beautiful pair of the special edition ones for sale here a couple of months ago for a reasonable price that I couldn't afford. Anyway, for months the was a very nice pair of version III (the latest) on USAudiomart with stands (!) for $2200. I was waiting to sell something so I could buy them (sound familiar?), and the day that I had the money in hand, I emailed the seller...he sold them that day. My heart sank.
They are a truly great speaker. I was dying to hear them with my 300b amp. Maybe some day. 
I’ve only seen 2 pairs of Dali Epicon 6’s for sale anywhere,and my friend grannyring bought one pair.

I haven’t seen any of the Epicon 8’s at all,probably a good thing because I will want them.They are a very new design but give it Time there will be some.

This whole thread is silly .... unless you know how many of each were sold up until about five years ago, their is no basis for comparison.
Oh jeez! I just had a response to this thread removed, presumably because I mentioned an item (long since sold) that I saw advertised on the other website where gear is bought and sold. 
That is really ridiculous!