Wow, interesting info, thanks. I've never seen that "high/low" flange hub. Not sure why they would have made it like that, with two different sized flanges, you'd then have different relative spoke angles on each side of the wheel, must have had a sloppy look. It would seem a lot better for not only aesthetics, but for overall tension balance etc to have the two flanges be the same. Perhaps this is why they did away with this high/low hub.
The front drum brake hub I have is the same as the one in the photos posted by elginkid. Both flanges are pretty large and are the same as each other, it's the "Large Flange Heavy Duty Fore-Wheel Brake" shown in the catalog page above.
The brake hub I have came on a `50's Phantom that I picked up, but there's evidence that this bike had been somewhat tampered with during it's lifetime and I feel I cannot trust the originality of the parts. In other words, I cannot say for sure that this brake hub originally came on a `50's Phantom, but it sure looks like a drum brake hub that would have come originally on a `50's Phantom.