Part of that is going to be the fact that a ton of the imported RHD's here are sports cars - Skylines, Supras, etc. and they are bought by 16 year old kids. 10 years ago I had the chance to purchase an R32 GTR (running and driving well) for 7 grand if that gives you an idea of the buyers.
That...
Circulating block heater is the way to go if you can plug in. Feed from the coolant drain and y-in to the top of the heater hose.
If you can swing it get a Webasto/Espar, expensive but worth every penny in my opinion. It gets extremely cold where I live (deep into the -30's) and my truck always...
I wouldn't recommend the fully hydro A442 if you have options, from someone who has a full hydro A442F. That is unless you want to shell out for an updated valvebody from wholesale automatics.