Dependable current production EL34 valves?

[Beer of the Bass]

I've got a late 60's Carlsbro CS100/8 PA head which I use for bass; it's a 100 watter using EL34s. I've been running Electro Harmonix 6CA7 valves as they were on special offer at the time I got the amp. I don't run the amp particularly hard, as the power stage stays clean, and I've always set the bias fairly conservatively. Everything in the amp is healthy, it's been re-capped and thoroughly checked over.
I've just had a valve develop noise issues, for the second time in only about 12 gigs - the first one developed random crackling and sizzling noises and got replaced, now one has started producing microphonic jangle through the speakers. I have a spare to replace the offending valve, but the next time I re-valve, what's out there that might be more reliable? NOS are out of my price range, so I'm wondering which currently-made valves have been more reliable for people.

[Mr. Foxen]

Shuguang.

What plate voltage is the amp running?

[Beer of the Bass]

[quote name='Mr. Foxen' timestamp='1333372507' post='1600680']
Shuguang.

What plate voltage is the amp running?
[/quote]
Shuguang are one I hadn't thought of trying, but I guess if they withstand Doom they'll be fine for my usage.
The plate voltage is at 500v, so it's on the high side but not outrageous. Space is a bit tight with the fat bottle 6CA7s, so possibly they're getting hotter than is ideal - though they've never red-plated.

[Mr. Foxen]

Maybe fitting a fan might help. Not sure where you'd tap the power from, but doable.

[3below]

500V should be ok. Remove power tubes, clean contacts, inspect closely, may be worth changing any suspicious valve bases. I have found JJ tubes pretty good. Then again my Sound City and Marshall still have original (as far as I know) Mullards in and are still good to go .

[pete.young]

I have JJ Tesla in my Burmans - KT77s rather than EL34s, though JJ make both. The KT77s are really good valves, might be worth giving them a try instead of the EL34s. Conventional shape rather than fat bottles.

[umph]

i like the shuguangs, not happy with jj's

strange you had problems with the ehx 6ca7's been running the ones in my roost for about 3 years now

[Mr. Foxen]

How close are they in the Roost?