I happened to saw some on some service 22 buses. They are:
SBS 970B
SBS 977H
SBS 983P
SBS once used SBS 0937Z and when I boarded the bus, I also happened
to see cameras, especially in the front of the bus. There could
probably be 6 on the bus, from what I can see on the screen,
installed on top at the bus driver's seat.
This goes the same for SBS 933J (Which I forgot to put,
sorry!).