Those were plastic molded replicas or something like that on the back in that episode. As soon as the Varuta showed up he dumped the prop. They looked like crap on the -19 to boot.
I never quite got that. There were so many VF-1's actually on M7 (in perosnal collections) they could have just used one of those for their little movie. But then again, Basara wouldn't have been able to do his song routine during the fight.
his guitar wouldnt fit in a vf-1 cockpit