I think I have a unique pick for Roland. Viggo seems to be mentioned more than anyone for the part, and while he is a very good choice - especially after seeing him in The Road, which kinda makes me think of Roland's world which has "moved on".
But I think Timothy V. Murphy would be a dead ringer. He could be Viggo's older brother, looking at him!
Both of those pics are taken from his IMDB page. I would SWEAR the second is of Viggo, but apparently not (according to IMDB anyhow).