Replacement tubes for C-J

Thank you Stevecham. That's great info. 
Much appreciated. 

Viva tubes is my go to tube vendor. Very reasonable prices and the match on their matched tubes is excellent.

I'll second viridian's recommendation of Viva Tubes. Good prices and great folks to deal with. https://www.vivatubes.com/
My other favorite source is Jim McShane. He doesn't have a pretty web site but just send an email or give him a call. He knows more about tubes than just about anyone, does meticulous testing and is a real gentleman. http://www.mcshanedesign.net/tubes.htm

Thank you all. I've ordered new tubes. It will be interesting to see how the old boy  performs with the new tubes.