Where can I buy beads like this?

This is a necklace I made with a friend (+ a pic of me wearing it lol).

We both have one of these and we’d like to make more but we don’t know where to get the beads, since we didn’t buy the original supplies ourselves. I hope you can see them well in the picture.

I don’t know if this is the right subreddit for this, if not I’m sorry :)