I'm trying to reconstruct a soundtrack for the 1938 serial 'Flash Gordon's Trip to Mars'.
Being low-budget, it reused cues from other films such as the ones below. Does anyone have them?

Black Cat - Heinz Roemheld
The Invisible Man - Heinz Roemheld
Bombay Mail - Heinz Roemheld

Werewolf of London - Karl Hajos

Great Impersonation - Clifford Vaughan

You've been here (http://flashgordon.ws/The_Music.htm), right?
Lo bitrate, and SFX, but here's all of it, for all three serials.
As far as I know I've never seen actual soundtracks for any of these.