Which Budget Friendly Floorstanders Next?

I just picked up a pair of Kef 107.2's for $1400 and they're pretty damn good! These have had the driver's surrounds replaced and crossovers serviced so they're in pretty good shape, you could probably find a similar pair. I've also got a couple pair of Martin Logans (CLS llz and Aerius i), just sold a pair of Maggy 1.7's and had a pair of Vandersteen 2Ce's - the Kefs are more than capable of holding their own in this group. The Vandersteens are really good too, you'll never go wrong with a pair. There are quite a few older top end speakers available that are in your price range now. 

<Elac dealer disclaimer>
Huge recommendation for the Elac UF5 and the UF5 slim.  Always amazed at what this 1000-1500 pair speaker system delivers.  :-)  I compared the UB5/UF5 to the CM5/CM7/CM8/CM9 and was shocked how much better the Elacs were, and for 3X less cost.  

They might be getting a bit long in the tooth but a well cared for pair of Gallo Reference 3.1's would always be worth a listen.

There are some Vienna Acoustics Mozarts (used) for sale that would be great in your system.