Vetterone,I owe it to you to keep this brief,yet,hopefully interesting.
My friend and myself have spent a good part of winter 2004/5 trying out the vast majority of phono tubes.This actually ended in June 2006.We tried the Amperex 6922 White labels PQ- which were fabulous.We tried Ediswan 6922 and 7308,also fabulous.All tubes were tested as ULTRA low noise.
We did try Teles,mega bucks,BTW--and were not real happy with these.A bit too lean for our taste.Also tried was Amperex 7308,very nice.A bit soft.In all honesty,and in similarity to your own findings,we got our hands on some KILLER low noise Siemens CCa's,which cost dearly,and these were definitely the best we've had in our phono sections.These tubes,to us,were so good that we may end our quest here,though I may still spring for a set of "Pinched Waisted Amperex".I don't think I can hold out, without at least trying these.ALL tubes had really distinctively different sounding signatures,as you must know.This is really a great way to voice a system to a specific taste,though many manufacturers won't let on to how effective NOS tubes can really be.
BTW-the guy "SAM" who sells on Audiogon,is very reliable,and seemingly honest.
Best regards!