I don't know the answer, however personally a well set up drum brake for the rears would be my preference, especially for the handbrake, as disc handbrakes tend to relax their grip as the disc cools down and cars have been known to run away on steep hills (I think this was one reason for electronic handbrakes on newer vehicles) although given your location maybe there are less steep hills to park on.

I agree from ease of working changing rear pads rather than brake shoes and wheel cylinders has it's benefits.
For me the best option was Disc rears with a mechanical activated handbrake brake drum inside the rear disc, so no hydraulic wheel cylinder to worry about, as some manufacturers Iveco Daily, Volvo etc.
When I ran 3.5 tonne Iveco Daily's towing a 3.5 tonne trailer I knew I could trust the handbrake on a steep hill with that set up.
They do need to be well set up and correctly maintained, so that has to be balanced with the ease of servicing of a disc set up.