You may want to try the cryoed tubes from CryoTone. I have bought the 6SN7's. They are extremely quiet. And there's an extensive trial / return policy. They're not NOS, of course.
12AX7 tubes for the phono stage of VAC Avatar SE integrated.
What would you choose ? Say, up to $500 for a NOS closely matched pair ?
Currently have Brimar military and don't like them. They are primitive and have recessed midrange.
I have Mullard long plates from 50s in the line preamp, RCA black plates from 50s in the driver and Mullard XF2 power tubes.
I was thinking same Mullard or RCA black plates but there might be something better to try.