Having a scanner or any non broadcast receiver in many countries is looked at suspiciously. The UK is a prime example .
I looked at the TRC website and even did some searches for common terms. It seems that agency is not concerned with licensing of permitted ransmitting services . Laws prohibiting scanner receiver may be codified in federal laws and enforced as a national security manner.
You might try to look at the Customs restrictions for Cambodia to see if anything you might consider bringing is prohibited. A discussion with the Consulate is also recommended. But you do run the risk that you might be tagged as a foreign agent .
If your interests include Amateur radio, that is a more easily understood concept in most countries.
Personally, if my job and safety were on the line, I would leave the radios behind and spend the first 6 months getting aclimated.
My wife lived in a Communist country and she told me having an antenna raised suspicion. She had neighbors that would report such things.
I travelled to Jamaica once with a Kenwood R1000 SW receiver and the guy at customs said he could seize it. He didn't, but they have rules exactly like the UK as they were once under Crown rule.
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