I recently purchassed a antique Magnavox Speaker (cabinet w/ 4 speakers)it has to be from the late 50's/60's??? It works and sound great but I believe the main speaker has blown out. Where do I go to find information on this speaker? All I have is the serial/model #. Where can I go to get the speaker repaired and get replacement tubes for it? Can it be any kind of tubes I can buy? I would greatly appreciate any information any one would have on this and where can I go to get this fixed and get backup tubes, thanks and I hope to here from someone soon.