Stern test or transaction (6)

I believe the answer is:

ordeal

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'stern test' is the definition.
'ordeal' can be an answer for 'test' (I've seen this before). I'm not certain of the 'stern' bit.

'or transaction' is the wordplay.
'transaction' becomes 'deal' (a deal is a transaction or exchange).
'or'+'deal'='ORDEAL'

Can you help me to learn more?

(Other definitions for ordeal that I've seen before include "Severly trying experience" , "A tough time or hardship" , "Unpleasant and prolonged experience" , "Loader (anag.)" , "trying affair" .)

I've seen this clue in The Irish News and The Globe and Mail.

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