Up for sale here is this beautiful NOS NIB Sylvania 5X4G coke-bottle rectifier vacuum tube, dated 1942.  I tested it on my B&K 747B tube tester, and it pegged the meter at 120/120, with no shorts or grid emission, on a scale of 0-120, where 65 is minimum good.  This is a gorgeous design and will look amazing in your amplifier.  It is guaranteed to work well for you.  Please see my pictures for details.

US shipping and handling is $4, and international is $14.  I accept Paypal.  If you have any questions, please ask.

I have a number of other tubes & sockets, collectibles, Magic cards, and vintage electronics listed--feel free to take a look!