Best 6922 tubes for DAC

I am thinking about replacing the stock Sovtek 6922 in my Audio Logic 24 MXL dac. Can anyone recommend NOS that would work well in this dac? Please try to describe sonic characteristic of the tubes you are recommending.

Rest of the system:

Joule Electra LA 100 preamp and Stargate amps, Merlin VSM speakers, Sony X707ES modified transport, Cardas and Stealth cables.

Many thanks!!