Below are links to user forums and businesses offering parts and services for antique radios.
Antique Electronic Supply
http://www.tubesandmore.com
Nostalgia Air (Schematics, Online Tube Reference, and Forums)
http://www.nostalgiaair.org
Just Radios
http://www.justradios.com/
Radio Daze
http://www.radiodaze.com
Renovated Radios
http://renovatedradios.com
Mouser Electronics
http://www.mouser.com
DigiKey Electronics
http://www.digikey.com
Online Components
http://www.onlinecomponents.com/
Philco Radio (Philco Information and forums)
http://philcoradio.com
Philco Repair Bench (Philco Radio Informaiton and Schematics)
http://philcorepairbench.com
Antique Radios (Radio informaion and forums)
http://www.antiqueradios.com
Play Things Of the Past (Lots of radio parts and Tubes for sale)
http://oldradioparts.com
Broadcasting History Guide
https://wyomingllcattorney.com/Blog/Business-Studies-Broadcasting-History