Looks like a combination of...
Emily Blunt and Alexis Bledel. If their faces were morphed together, they would come up with Claire Foy's face. I saw someone else post Anna Friel on here, and I can see some resemblance there as well, so I'll throw her in there too.
I know there are posts like this all the time on imdb, "So-and-so looks just like ____!!!" but it was too striking for me to not comment on.
What does everyone else think?