Given the input impedance of your amp, a tube pre with balanced output capability is probably your best bet. Definitely check out the Cary SLP-05 if in your price range.
Need help with a Tube PREAMP.
I currently use a Solid State 2 channel AMP with an Input of 20k(unbal) 40k(bal). I am looking for a great Tube PreAmp for around $2500 that would mate well with the AMP. any suggestions would be greatly appreciated.