Bargain, as the order sent abroad (5-5)

I believe the answer is:

horse-trade

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'bargain' is the definition.
(thesaurus)

'as the order sent abroad' is the wordplay.
'as the order' can be anagrammed to 'HORSE TRADE'.
But, I'm unsure how the anagram is indicated.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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