The most common and most likely answer to this crossword clue is the 5 letter word RIELS
R
I
E
L
S
Buddy explains!

The straight part
We know that "notes from Cambodia" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case notes from cambodia = riels.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RIELS mean?
RIELS noun- The monetary unit of Cambodia, equivalent to 100 sen or 10 kak. Symbol: ៛