Best way to spend $1000 on used bookshelf speakers?

Vandersteen VLR's are my pick.
Made to be near corners, like true bookshelf speakers.
CT or non-CT they can really be made to rock. Just add a Belles Aria Integrated, some good Audioquest cables and you're set.
I use mine like monitors in my office and am very happy.
Bob

When shopping for used speakers I prefer speakers that have sealed enclosures -- because you never know what insects or rodents have crawled into the enclosure.   Also, typically sealed enclosure speakers can be set closer to the wall.    In my opinion a speaker that can be set closer to the wall will be a more acceptable with the wife.       A speaker with a higher sensitivity can be paired with smaller and less expensive amplifiers.    Purhaps Klipsch would be a good place to start looking.    Also, smaller and cooler class D amplifiers is less obtrusive in a living room than bigger and hotter class AB amplifiers.   

I have Focal Arias powered by an Audio Research VSI60 tube amp and in my opinion the sound is pretty nice.

Meant to say Focal Aria 906

op

i personally would buy these

https://sfbay.craigslist.org/eby/ele/d/berkeley-spendor-speaker-sp1/7379408163.html

(except i have 2 pair already)

but these may not rock out well enough for you