If Jackson needs an actor to play a much younger Aragorn in some scenes of the bridge movie, he would do well to check out Taylor Kitsch who plays Tim Riggins on the excellent TV series FRIDAY NIGHT LIGHTS in the US. Although he was born in 1981, he plays a high school senior on the show and his ability to underplay scenes is amazing. He acts from much the same school as Viggo Mortensen. Plus he has the facial structure to make him believable as a young Aragorn.
www.taylorkitsch.net