Vintage tube amp tube recommendations please.

I have a Fisher SA-600 that came with new EH EL-34's It sounds awesome matched with my Threshold for bass.
At this time Im looking to upgrade the 12ax7 and 12au7 tubes.
Im looking for current production tubes or NOS or used tubes for fair price.
I dont want to spend more than $10/tube.
I dont need a tube with good bass as this amp will always be run with a SS amp for bass duty.
I switched out the 12au7 mismatched tubes with my yellow stamped Sylvania tubes.This fleshed out the mids better.But Im looking for better :~)
The 12ax7's are a original Fisher and the other I cant tell.
Im looking for a very clean and full midrange that throws a large soundstage.
The amp has 2 rectifier tubes.How important are these? Suggestions/replace?
Thank you.
Your original fishers are probably either mullard or telefunkens. Look to see if they are made in England or if they have <> on the bottom for telefunken (it will be on the base of the tube inside the pins.

$10 won't get you much for tubes. It's well worth $50 to $75 for an NOS pair of telefunkens or mullards. The mullards may have a sweeter sound but overall, telefunkens are great. Think of it this way, you will get 5000 to 10,000 hours out of 12ax7's/12au7's. So, for $75, that will cost you about 1cent per hour.
David99, Just to make the waters a bit murkier...Elevick really covered this suject well and if you would like a little good reading check out this website. It is well reviewed amongst A'goners. Although he leans away from the highly touted Telefunkens, Joe has a vast experience and knowledge of the tube roll game. Enjoy!
Thank you for your repies.There is only 1 fisher tube in my amp and it doesnt have the Tel diamond on it.Im wondering if anyone has had experience with Ei Gold Elite tubes?
For great reading, go to They have some great articles on tubes.

By the way, for newer tubes, I like golden dragons and some svetlana's. I haven't had the pleasure of trying the reissue of mullards yet.