After Starlet O'Hara's comic book was canceled, more stories were published by the American Comics Group. The previous series had been at Better/Standard/Nedor/Pines, but both seem to have been the same company. The history of the American Comics Group was covered in ALTER EGO #61, a preview of which can be seen at http://twomorrows.com/media/AlterEgo61Preview.pdf .
This particular story was published in COOKIE #24, in April 1950.
"Platters" refers to phonograph records.