Appreciate the info on the concentric H.L. and as you said windy I'm building confidence.
GOOD NEWS and want to thank NDkid275 for the tips which led me to get the rear drums off!!
Photo of brake in link below:
https://1964chevyp10.blogspot.com

To sum it up: (1964 Chevy P10)12 bolt rear axle that I believe is stock from 1963/4 with 6 lugs for the wheels. The measurement of the diameter to the outside of the shoes is approx 11inches. The width of the shoes is approx 2 inches.
1) brake shoe holder gone on one side
2) star adjuster does not turn
3) no locking mechanism on the star nut adjuster? Is this OK as maybe its older style of brakes before self adjusters or are the self adjuster bits missing?

So, at minimum, I am in the market for new shoes, and a hardware/spring kit for the rear brakes. Based on my brakes is there a particular vender that would be good to buy from?
Any other suggestions/ideas are greatly appreciated as this is my first time doing brakes.