Kamen Rider 3's actor?
 

Actor Takahashi Katsunori and his wife were being spotted at Kamen Rider x Super Sentai Live 2015 among the audiences today.
The actor has been showing interest to play a villain in Kamen Rider since 2011, and numerous rumors has been out for him to be in the Rider series since then.
Until there are further announcement this is just speculation.

http://s.cinematoday.jp/res/A0/00/25/A0002539-00.jpg

That would work for me. Rider 3 cannot be a 20-something prettyboy.