[Amps] 3-500Z tube recommendations

[Jason Buchanan]

I am thinking about purchasing some new 3-500Z tubes for my Drake L4 - 
just wondering what recommendations anyone had.  Currently the amp has a 
pair of 3-400Z Amperex graphite tubes from 1968.  They work fine but one 
glows a bit brighter than the other and I would prefer to have another 
set anyway.  This requires the purchase of new chimneys so this will be 
a two phased approach.

I made the mistake of buying some old 3-400Z tubes for it only to find 
out that they had suffered a wee parasite...  so no more 36 year old 
tubes for me!  Not unless they are properly tested beforehand!

So what does anyone/everyone recommend?  RF Parts comes to mind but 
would like to hear the experiences of others who purchased from other 
companies.


Thanks

73 Jason N1SU