Unfortunately JJ Electronic is the only 6386 tube manufacturer in the world at the moment, and they do not want to match tubes, so I have to buy a lot of them to be able to make nice sets for all the FAIRCHILD work that I do worldwide :
I am more than happy to give you a discount if you can supply me with original new old stock tubes :
It only needs to be two sets of four identical tubes, perfectly matched, none microphonic, and low noise...
Here is a list of all the JJ Tubes serial numbers that have failed on me so far, it seems like year 2014 was particularly bad :
You can send your Tubes for testing and matching at POM AUDIO DESIGN if you like.