Here are more.......the Flag pin with star symbol was and still is very common.
https://i.ebayimg.com/images/g/g4cAAOSwcN1aaJ6J/s-l300.jpg
Ebay? So they’re available for purchase by just anyone? Is that what you’re implying?
All the pics you gave is a yellow star with the center showing a circled stars and strips shield. The pin we’re looking at on this person behind Biden is a circled standing human figure likely of Columbia.