[Arran]

The cabinet looks pretty good, other then the grille cloth near the bottom, I believe you can get that pattern again. I would have to check but I think that the 39-45 was the largest of the non mystery control U.S models for the 1939 model year. I think these had a tuned RF amplifier stage, the next year Philco went all in for the dual IF amplifier trick like car radios, and transistor radios used, more gain, slightly less selective, but definitely a cheaper design. The other differences are that they use G style tubes, later models used loctal tubes, hence the tube shields, and they used rubber/gutta percha covered wire on the power transformer. Another common failure in these sets are the audio output transformers, AES has generic replacements, or you can try fleabay, or finding a used one on some other set.
Regards
Arran