Looking for a tube Preamp new or used for under $2000...

Hi all,

I am looking for a tube preamp for my Parasound A21 amp. I currently have a Parasound p6 preamp, but have been told that a “Tube” preamp not a SS preamp would make a huge improvement. My budget is $2k however, I would prefer to spend less! I am looking at McIntosh and audio research preamps. I am willing to purchase an older preamp, but not one that I would need to send it into be serviced. Any suggestions? Thanks!