I was relaxing the other day, reading Sword of Sorcery #2, a fantasy book from 1973 starring Fritz Lieber's Fafhrd and the Grey Mouser, written by Denny O'Neill and drawn by a young Howard Chaykin. (I do love me my early 70's DC fantasy books - Stalker, Beowulf, Sword of Sorcery, Starfire, etc).
And what do I see at the back? An old ad for patches of DC characters ... including Supergirl!
For a mere $1, you could be the owner of any of these! If only I had a time machine.
This is pure 70s Supergirl - hot pants, ballerina slippers, puffy sleeves. Who wouldn't want this on their backpack or hoodie zip-up sweatshirt.
And I am pretty sure I know the source material.
Art Saaf's splash page from 1972's Supergirl #1.
I wish I could find a picture of the actual patch. But the ad will have to suffice.