Replacement EL34 Mullard valves for Leben CS300X


6+ months ago I succumbed to temptation and bought a used CS300X over the internet from a German dealer. The unit was in very good condition and the sound quality has been excellent. Sadly one of the Mullard EL34 output valves has now failed and a second is about to go. I have no idea how to source a replacement quad set - though I suspect scarcity is the least of my problems. Finding genuine NOS at a reasonable price feels like a very tricky business. Does anyone have any guidance?

PS - I have bought a quad set of Golden Dragons to keep me going. I suspect there is some run-in required but it does seem as though some of the original magic has gone.
richardjames
Genelex/GL KT77s or Tesla EL34L Blue.
Have been through them all and those 2 have been the best for sound and reliablity.
guitar amp thread
http://www.eurotubes.com/euro-j.htm

the tube store (canada )
http://thetubestore.com/el346ca7types.html

tube subing website
http://www.pacair.com/discus/messages/23/23.html

vaccumm tube world ??
http://www.vacuumtubes.com/6ca7.html

I'm not endorsing any of the above for purchassing or sourcing tubes from as I've no personal experience with most of them. I figured these links would help inform so some more intelligent choice could be made thereafter.

Only thing I'd also look into is the plate boltage or bias the maker of the amp intended for the tubes... although some are 'drop in exchanges, I'd prefer to know if I'm going to go another way... often minor voltage variances can and are acceptable.

I also agree with the mini remarks on the CED winged C the tube store posts.

if you need EL84... HAPPY GOOGLING!
Apologies everyone. It does appear that these are EL84's. I have no clue(as is even more obvious now!!)whether these tubes are even more challenging to find alternatives for.