Is there any authentic Chan Buddhist lineage operating in the West/Europe? I mean Chinese Chan Buddhism, not Japanese Zen or Korean Seon. If not, what is the best course of action if one wants to become a monk in Mahayana Buddhism, but not in Theravada and not in Vajrayana? I am especially fond of Master Xuyun, are any of his disciples still around?
There's only two Ch'an lines active in the West that I know of, the first one founded by Hsuan Hua. Its headquarters are in California. It has branch temples, for the West mainly in the US, listed on this page.

The second is the Western Chan Fellowship, who actually list Xuyun in their lineage, and has branches in the US and Europe.