If my memory is good (which it isn't!), the GE tube is used, but quiet enough in a Sony C800 clone circuit. The other tube is NOS, no idea how quiet it is. Of course your circuit is quite different!
Hi!
To revive an 8 year old thread...
I am on the same quest for a tube for a noisy Philips EL6052 / Schoeps CM61 mic. I am hoping it is the tube as well.