Lite Audio GA-31a phono preamp, is it a clone?

@tablejockey  looking at the project diagram, could you tell me which are the most important slots?

I'm not qualified to interpret that schematic, perhaps noromance  or someone else will chime in. 

If anything it's going to be just a pair(L/R), not all 4 that will make a noticeable SQ  difference? You can always just experiment when you get it. You'll be out just two pricey tubes instead of 4.

@tablejockey ok, thank you very much!.

I can tell you that the driver tubes will be the most important for low noise then the output tubes second but i would listen with the stock tubes if you hear any noises or tube rush go for old stock tubes it will be much more quiet and the sound will improve.