Battery Replacement - Tamiya Avante 2001 Quick Drive

I'm trying to revive my old childhood Tamiya Avante. It used to run on 8xAA batteries but would like to put in a lithium cell if possible. I have a few of the 18650 batteries laying around. What would suffice? Or am I better off buying a 2s/3s I see on drones and things? Thanks for the help