TVNZ operates as such, with three commercial channels. It just happens to be owned by the NZ Govt, who take a (small) divvy each year.
Public television is served by a funding agency, NZ On Air, which funds programmes across (in theory) any channel (including radio, online, music videos, Radio NZ).
Quite frankly, apart from a few weeks when television first officially launched back in the sixties, NZ television has always been commercial (apart from the few non-commercial nights, which were phased out to eventually what we have now, non-commercial Sunday mornings).
Long live the ABC!