There's no block for getting actors like that. You can do it with code, but actors have to be referred by ID, not by name. Only Actor Types can be referred by name.
I like to create Actors on a scene at runtime and it would be great if I could just tag each one with a Name at creation for messaging later.
Are you using Stencyl 3? The behavior was previously pre-3.x only. I've just shared a 3.0 version.
public static var namedActors = new Map();