I like the idea of comics, certainly as already mentioned, it would fit or rather not seem out of place for Zodiac. There's other more loosely related Zync here too. There's the also a little pseudo mixing of 'mysterious' or 'supernatural' concepts. The wheel made from mysterious wood from Egypt. rumored to have been made for King Solomon, the ruler of the Djinn. Oh and lets not forget 'Red Mask' .....or 'Phantom'
I'm not sure either about the cattle brand. Although, that's just me. It's is the closest thing I've seen as well but I guess until I can understand it's purpose I'm unsure. If it is a cattle brand or inspired by one then I would be inclined to assume that Z has nothing to do with cattle or ranches? It seems too obvious but, again assuming that it is, what's it's reason or message? Might not be one, maybe he saw a brand and thought, eh that'll do for style for new symbols. Or, taking it as one, does it translate into anything?
Great find though and I like the age of the comics, possibly from the right time period to be from his childhood, a good place to draw inspiration from because they are visual and slightly out time in respect being connected to anyone.