Tube Preamps.....

I am running 2 GFA 565 Musical Comcepts modded Amps with Vandersteen 2ce v2. I am looking for a good quality tube preamp. With or without a built in dac. Should I stick with shopping for a used Mac? Or should I look at others also. Suggestions? Like to keep it under $3000. Could stretch to 3500. Thanks for your input.