Vintage tube suggestions


Need help with tube selection. What would you consider a great value 
(budget of $100 per tube) for 12AX7 vintage tubes? Application would 
be preamp, and possibly DAC.
markj941
thanks rotaryphone Will any Telefunken 12AX7 do? Are there a variety to chose from?
IMHO, one of the best 12AX7 is the Mullard CV4004.  I have drawers full of tubes and these have always sounded great.
Telefunken Black Diamond ECC83?

I'm pretty sure that rotaryphone is talking about NOS Teles, not new production, which the Black Diamond Series is.
It is late 50s to 60s NOS Tele is what I am talking about. Mullard is also great as well. Mullard is little bit richer in the mid then telefunken. In my system, Tele has a better and bigger soundstage then mullard but less creamy.  Only new production 12ax7 I like is Generex gold lion brand.