Best 40 to 50k used speakers

SO, do we assume a 40-50k speaker pair will go into a bespoke listening room???

This is not quite in the price class, but I've read good reviews of these speakers and amps: http://sanderssoundsystems.com/products/price-list

stenheim alumine 5 .
AudioArts NYC once had one for sale on AudioGon.

@thieliste

FYI on Alsyvox - https://www.usaudiomart.com/details/649661765-alsyvox-tintorettos/ (though a dealer ad)

My second fav speaker is the Thiel CS3.7, which you seem to be moving away from. What an incredible sounding speaker.

My favorite is the KEF Blade and I am looking forward to hearing the KEF Reference and Blades with the new Meta stuff. Could be a good choice coming from your Thiel background.

A Vivid speaker may also be something you like. I love the Vivid lineup too but I think KEF gets you close (or better with the Blade) for less dough. The new Magico A5 is also something I would like to hear, though I do not like Magico as much as Thiel, Vivid, and KEF, I maybe in the minority in that statement.

The Yamaha NS500, though classified as a bookshelf plays well in big spaces.

Everything I listed comes from big companies who may give you the benefit of Economies of Scale in their design and construction of speakers (Vivid maybe from B&W work).

There are way to many variables to give you the answer you seek.

What are the dimensions of your listening room?
Is it dedicated for audio or multi-purposed?
What are your listening tastes?
What is your upstream equipment?
What speaker performance qualities are important to you?
What speaker aesthetics are important to you?
And as Yul Brynner said, "Etcetera, etcetera, etcetera."