I had a look for them, but there is nothing that accomodated the side air-bags.
Renault apparently make them, although they dont sell them in the UK because they are unpopular for some reason. They cost £1500 each (!).
I got some fake leather ones from Halfords, & fitted the rear seats as standard, but cut the back and lower sides off of the front seats. (leave the front with the stretchy tags)
The back is pinned in by the headrest, the lower back is held in by a stretchy tag (that came with the seats) and the front seat part is held down with the stretchy tags.
Looks a bit crap, but it was the best/safest thing I could think of.
Or, you could get a couple of those nice brown bead seat mats, as they would keep him off of the seat and would also leave the airbags free.
(You could just cover the airbags, but think about personal liability in the event of an accident.)