I looked at some chick pics of the Starlight’s and it looks like females have eye stripes. Mine don’t. Dunlap (one of the two hatcheries the store buys from) has “Golden Sex Links” aka Bovan Browns. https://dunlaphatcherypoultry.com/product/golden-sex-link/I bet they're Starlight Green Eggers actually. They totally slipped my mind and look very similar to Red Sexlinks but hatcheries consider them "rare."
Bovan Browns were developed in the Netherlands, so maybe that counts as rare? They look closest to the pics of those chicks or the ISA Browns. The store also had some ISA Browns that were 3-4 weeks old there as well, so that seems like it could also be a likely possibility.
There were 4 chicks in the brooder - 3 of whatever kind of chicken these are and 1 chick with interesting coloration and cheek puffs - some sort of EE with a fancy name, I’m guessing. Anyway, the EE chick was quite a bit older, so I think they put them all together so the EE wouldn’t be by itself. I had a friend tell me there were chicks for sale there because she’s been there earlier that day, and that one little chick was all by itself and peeping very sadly. That’s my theory, anyway, and I’m glad they moved the chicks together, although it probably means I paid more for a not-rare chick than if I’d gotten it from a bin labeled sex links. Oh well.
I’d love to know what type of sex link they are, just because I’m weird like that, so keep the ideas coming!