For that price you could get into a pair of used Von Schweikert Anniversary MK 2 speakers. Mine sold quickly at about that price. I owned them for years and they are really exceptional. I left only to upgrade to the $60,000 Von Schweikert VR 55 Aktives. I think they would meet your efficiency standards.Call VSA and they may know of a pair available and can answer any compatibility questions knowledgeably.
$16K new/used speaker question?
Opinions on options for full range, 8ohm, 90db or above speakers. So far I have heard and liked both Devore GibbonX, and Acoustic Zen Crescendo's and really like them both a lot. I'm using an all BAT tube system with the VK-150se tube amps. Any thing else I should be listening to? I've heard the Wilsons sound great with BAT gear, but on paper they look like they would be really rough on my amps.