Do the tubes have to be matched?

Tommy,

It's imperative tubes are tested -- . End of subject. As far as your 6BM8 goes -- how about the European equivalent ECL82?

Tommy583
Do a Google Search for Jim McShane tubes and he will be one of the best sources to deal with and he is recognized as one of the best in this business. He has excellent knowledge of a lot of gear out there and he has kept me
happy with all my tube gear for sometime now.
He will help end the madness that you are going through. There are other reputable dealers out there but none give you the warranty and service that Jim offers. You will smile with the service you get and the quality as well. And he has some NOS tubes too.

Ponnie,
Thanks for the tip. I emailed him this morning. His site was helpful and so were the links off it.
The tubes i was talking about above were in black and yellow Sylvania boxes that have a made in England stamp on them. The tube itself says Sylvania made in england, tested in USA. With codes KBV ef, OG2 B9B3 also on them. The guy at the store said they were made by Mullard.
I've never seen these one's on the net. I was thinking maybe i'd found some real rare nos tubes, but like Ontjesr said they guy can't test them let alone match them. If i could find someone with a tube tester around here that could help.
Tommy

If you really want those tubes, you can buy them and send them to a tube retailer and have them tested and matched for a small fee. The code seems to indicate that they were made by Mullard at their Blackburn plant. Andy at Vintage Tube Services or Charlie at Vacuum Tube Valley can perform the tests and tell you if they are microphonic or not.