I would think your best bet for a kit of that would probably be in the Italeri range or possibly the G.222 has been around long enough that Esci may have done one at some point.
I suspect, whatever the case, it would be a Europe only release and you'd probably be looking at a special order to get one.
Try the Italian manufacturers first, The Italians made that plane, they'd be the best bet for model kits of it.