Isn't Lucas injured right now? Last I saw he wasn't playing for the Reds second XV, either.
There's a few non-starting halfback options in Aus for the Rebels that would be acceptable, I guess: Lucas, McKibbin, Holmes, Phibbs, O'Young, Kingi. For a new team like the Rebels Lucas in particular would be my choice out of that lot.
If I was the Rebels, I'd also be talking to Morahan right now, and some other fringe players like Daisy Dennis, Adam Freier, Dan Palmer, Nic Henderson and Greg Holmes.