Changing Tubes in BAT VK-300xSE Int. Amp.

One of the original SOVTEK 6H30n-EB Tubes in my BAT VK-300xSE Int. Amp. is on it way out.

Is the NOS Russian Mil.-Spec. 6H30p-DR ($80-each) the best sounding replacement Tube for the 300xSE?

I’ve also seen Cryogenically Treated SOVTEK 6H30n-EB Tubes for $28-each, and Electro-Harmonix 6H30Pi Gold for $24-each. Do either of these Tubes offer an advantage over the original?

The direct-replacement SOVTEK 6H30n-EB is the least expensive at $19-each.

BAT told me to just replace the defective Tube, and that there is no advantage in replacing both Tubes with a Matched Pair.

This is my first Tube replacement on this Unit. Any advice would be appreciated.
Those input tubes are critical. BAT has told me matching helps (on other models). I'd by two new matched sections and matched to each other tubes.

Keep your current good tube as your spare. Also, I'd clean the tube pins and sockets with something like Kontak. I light sanding using 400 or 600 grit paper on the pins should help a little to.

Sorry I can't help on the dr vs eb vs pi types.