I don't know anything about the sources for the films you are looking for but
you might also think about Zultan Korda's SAHARA, starring Humphrey Bogart
and scripted by John Howard Lawson. It embodies much of the popular front
ideology and is surprisingly progressive for a WWII film. I use it to teach
about the Hollywood Ten and know that it is commercially available on video.
 
--Henry Jenkins