Can't help you, but have you been to the antique radio forums? If they can't help you, they might be able to tell you where to go. There ought to be some slopover in parts and technology I would think!

Here is a link that might be useful: http://www.antiqueradios.com/forums/viewforum.php?f=20

Hi. Most old-time speakers would need re-coning.Finding two that would work on a real time basis,they still would be re-built ,not NOS.Bite the bullit and buy new,even old cars need new tires
john