Except they do…Pacific Blue for example had a couple of aircraft that didn’t have any stowage compartments in the ceiling. The rafts were in the overhead lockers instead.
As far as I’m aware all Qantas 737s including the “classics” have compartments in the ceiling for rafts, but only the aircraft with PTVs have rafts fitted. If I recall correctly, rafts were taken out of the non-PTV aircraft a while back as a weight saving measure and these aircraft purely operate domestic. VH-VZW, as referenced by Melburnian, is a sky interior aircraft and would have the ceiling compartments.