If this is to be believed, the casting has been narrowed down substantially: http://makingstarwars.net/2016/03/final-shortlist-of-actors-for-han-solos-story/

Ehrenreich and Egerton have both been mentioned in this thread already, if memory serves. I don’t think I’ve seen a single movie with any of these guys so I can’t pretend to have much of an opinion, but I don’t think Reynor looks nearly as much like Harrison as the other two.

EDIT: that’s a bad photo of Reynor, he’s much closer to Ford in his IMDB photo.