Medium is the Massage; Gutenberg Galaxy would be my top 2 recommendation given what you wrote.
Take Today: the executive as drop out with Barry Nevitt
From Cliché to Archetype with Wilfred Watson
and finally,
Culture is Our Business, the last book he did solo [the one with WWIII being a 'guerrilla information war']
Also, if you're feeling philanthropic: I'm screening McLuhan's origin story at the Park in the place where he began University in Winnipeg.
At the very least watch the trailer and bask in the prescience of McLuhan yelling Fake News in 1969
I initially thought that was a typo. For others reading this: it's not, it was a collage-style collaboration between Mcluhan and graphic designer Quentin Fiore. That's really cool, I will have to check it out.