I know we already suspect who the mole is, but I still found this tweet by Carter Page referencing 5 eyes interesting,
"No @JackPosobiec, not me. But if what I'm hearing alleged is correct, it's a guy I know who splits most his time between inside the Beltway and in one of the other Five Eyes countries. And if so, it'd be typical: swamp creatures putting themselves first."
https://twitter.com/carterwpage/status/994869075993157635