Hi,
I did not know this but the late series ST165 (88-89) was optional with a sat-nav system installed, and in the one I know about, it has a TV reciever as well.
Who ever told you they were optional is talking shite.
The only way they were optional was if the owner bought an aftermarket and installed it.
Probably came out of a Lexus LS400 (or Toyota Celsior as they're called in Japan)
Think about it. GPS/ Sat.nav only came out less than 10 years ago.
ST165 is at least 15 years old.
Oh and the Japanese use a different system of TV called NTSC.
OZ uses PAL so it won't work either.