The Helen of Toy company widely advertised their Civil War figures (knock-offs of the Giant brand) in boys’ comic books in the 1960s. I answered the above ad and still have these little ACW figures forty years later!
Does anyone remember the Giant brand of miniature plastic Civil War toy soldiers? They were approximately HO 1/72 scale, and were molded in Hong Kong using fairly sturdy plastic that has held up 40 years later, with very little cracking, stiffening, or breakage. I had hundreds of these little guys, which made up my first miniatures army before I switched to lead-pewter alloy figures. Many of the figures used the same poses as the 54mm Marx Civil War playset figures, only in a much smaller scale.
I remember buying these figures at various times over a 3-4 year period with money I earned from chores (money that I had left over, that is, after buying baseball cards and DC Comics!). Some of the Giant figures came in plastic bags (an unsually heavy vinvyl bag IIRC), and others were on blister packs with colorful backgrounds.
Copies of the Giant figures from the Helen of Toy company could also be purchased from ads in leading comic books. For example, there were ads for a Civil War fort set which came with a printed, thin vinyl terrain map, exploding bridges, and rules for what became the first wargame I ever played.
These little figures can still be readily found from vintage toy soldier dealers, as well as on eBay and other similar on-line auction services. In a couple of years, my grandson will be old enough to play with them, and a third generation of Minguses (Mingi?) will enjoy these classic toy soldiers.