I started this inquiry and would like to pass on what I've found.
Someone mentioned "joe's tube lore" and he had quite an extensive cataloguing and evaluation of diifferent tubes. Going off of this and my own experimentation--Amperex 6dj8 PQ (premium quality) tubes made in US, white or orange lable, but definately the US made ones. They make the siemens tubes sound metalic and thin by comparison. I've bought a few at around 30 bucks or so a piece. Let me know what you think if you ever try 'em.
ron