The most common and most likely answer to this crossword clue is the 4 plus 5 letter word FAIR TRADE
I've seen this crossword clue in The Times
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More clues leading to the result FAIR TRADE
- Principled purchases in market rated adversely
- Ethical business — or one getting some taken for a ride?
- Just nip back east for such ethical products
- Cast adrift are legal dealings
- Market rated badly for equitable dealing
- Shy ethical dealing?
- Fat raider abandoned principle of decent business deals
- Dash around after blonde European, thus giving producers a proper deal
Buddy explains!

The straight part
We know that "Principled purchases" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case principled purchases = fair trade.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.