Supergirl gets introduced in Ame-Comi Power Girl #3, and she has a ton of KO/sleepy scenes! First, she is discovered unconscious in a pod by Power Girl.
Afterwards, they are immediately attacked by robotic enemies of Braniac. Supergirl is placed in a green energy force field, which contains a sedative!
In Ame-Comi...
Captain America and Diamondback get knocked out while having a nice dinner at a restaurant. They wake up chained to a wall and in their respective costumes.
Red Skull also "kills" Diamondback in this issue, but it turns out he just kills a cyborg version of her. I included that scene, but it's kind of violent....
In this manga about mech robots, a boy and girl couple get knocked unconscious early on. A big robot lands near them and blows them to the ground. There's a good unconscious and wake up scene involving the girl.
The Scarlet Witch battles the villain "Necrodamus", and is KOed. This scene is from Avengers, Volume 1, Issue #128 (Marvel, October 1974)
Source: My Collection
Here is a Duo Damsel scene from "Superboy and the Legion of Super-Heroes", Volume 1, Issue #193 (DC, February 1973). She gets blasted out cold, plus there is a decent wake-up scene. I included more pages than just the KO because I thinks she looks really hot in this costume.
Source: My Collection
From the pages of "Superboy and the Legion of Super-Heroes", Volume 1, Issue #207 (DC, March-April 1975) -- Light Lass gets karate-chop KOed, while Shrinking Violet is shown unconscious (the actual KO was, sadly, off-panel); but she looks really good getting tossed around by Superboy, who has been mind-controlled into ...
Here are some scenes from Avengers #120-122 (February-April 1974) -- the Scarlet Witch and Mantis are KOed, and Wanda eventually exacts KO revenge on the villainess Virgo!
Source: My Collection
Cavewoman is choked unconscious by another equally voluptuous woman. It looks like something Gytalf2000 commissioned :-)
There's also a great alternate cover from Budd Root, which looks like an unconscious Cavewoman (or just really tired).
This scene from the August 1974 issue of the Avengers is a "gotcha" cover, since the Scarlet Witch was not KOed in the actual story. But she looks great in that unconscious pose in the Vision's arms!
Source: My Collection
The Scarlet Witch is felled by an energy discharge as she comes to the aid of the Vision. The Kree's Sentry captures her, and places her in bondage. a nice scene from the early 1970s!
Source: My Collection
From a recent European comic. The cover shows a woman being dragged by her hair.
The story starts with a girl waking up in a big spider's lair. The girl is bound with the sticky webbing.
Supposedly she was KO'd in the previous issue by the bug, but we don't see it.