Hello Gregory Walsh!
Sorry for the lag in responding (you may have figured out that discussions in Conversations of a Higher Order unfold at a more leisurely pace than the frenetic speed of social media).
I’ve assembled a few selections related to the çakras, but there are more – one of Campbell’s favorite subjects. Here are a few books, audio lectures, and a video:
Books
The Mythic Image pp. 331 – 387 (published in 1974 through Princeton University Press, you may find this in bookstores)
A Joseph Campbell Companion pp. 109 – 116 (or you can purchase and download the eBook and search the text)
Audio Lectures
Imagery of Rebirth Yoga (Lecture I.2.4)
The World Soul (Lecture I.2.5)
The Sound AUM and Kundalini Yoga (Lecture II.1.3)
VIDEO
MYTHOS II: The Shaping of Our Mythic Tradition
Lecture 4: The Way to Illumination: Kundalini Yoga and the Seven Chakras (I linked to the Mythos II DVD on Amazon, but the single lecture is also available to stream for $1.99 on Amazon Prime)
I trust that helps.