+1 for Zu Dirty Weekends - I run them with a 15 wpc Cary 300B SET integrated. The DWs were $1K with the base finish when I bought them 15 months ago. I team them with a pair of SVS SB1000 Pro subs which were less than $1K. This is a nice $2K combo that sounds excellent with acoustic, rock, blues and jazz tunes in a smaller room...15x15.
The DWs also sound wonderful with an 18 wpc First Watt SIT-3, which is solid state but has some tube sonic qualities. The SIT-3 is used primarily in my main system with a PrimaLuna tube preamp running Belle Klipsch speakers and a 2x12 SVS sub, but in a much larger room.
I also have a pair of Heresy I's and a pair of Heresy II's which both shine with these amps and can be found for under $1K online. These, also matched with a sub, would sound great with a tube amp, but not as nice as the aforementioned Heresy IIIs or IVs but easier to locate at a reasonable price. Bob Crites has updated crossovers etc. that can help to modernize these older unit.