Tube upgrade options for Dodge 8 preamplifier?

Agree, the RCA 12ax7 BP are very nice. Also Sylvania 12at7 BP are nice too. Westinghouse 12at7 also good. Plenty old tubes that test good are out there.

NOS can be hit or miss especially if you are inexperienced.
Try these. http://www.thetubestore.com/Tubes/Genalex-Gold-Lion/Genalex-Gold-Lion-ECC83-B759

To answer your question about the RCA tubes. Obviously, there are many variations. I have found them okay but flawed. They seem a little constricted. If they were a wine, they'd be Malbec.

Have you heard the pre amp? Does it sound bright to you? Just curious.

I suggest you listen to it for a few months and get it broken in before making changes. You might even like it.

I own a Doge 8 and installed Genalex Gold Lion 12AT7 tubes. I've been running the GL tubes in preamps for ~4 years and have always enjoyed their sound. They are very well balanced and fairly well extended on the high and low end. Bass is not overly bloated and comes across as quite full, though the high end may seem slightly rolled off. Note that when I say rolled off, it's not severe like JJ Tesla tubes. Considering the Doge 8 is so transparent, trimming a little off the high end works well.

Ditch the stock chinese tubes as soon as you can. would you buy a Porsche and put crappy tires on it?

NOS Mullard 6201s seem to still be available from Upscale…A great 12AT7 to be sure (I also have a pair of 4024s which sound pretty similar and have been relegated to "backup" status as I prefer the gold pin 6201s). I also found the GL 12AX7s (Russian version with matched sections from thetubestore) are serious bang for the buck as they're transparent and reliable…not particularly expensive. Interesting article at thetubestore site regarding cryoed stuff…they state why they don't think it's necessary.