I think they're only sold during the winter, but, I'm looking for a set.

It'd be great if anyone had a set.

They're called Tortoise Specs.

They're also only available from a fashion store that opens once you've fully upgraded the Nooks' store, so you'd need someone who's messed with their system clock enough to not only make it winter, but also get through all the shop rebuilds, and also go through enough random stock selections to get that one item to show up. Looks like you might actually have to wait until winter when lots of people can check lots of versions of the store :(