Paying for foundation coppers (7,3,4)

I believe the answer is:

footing the bill

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'paying for foundation coppers' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'paying for foundation coppers' is the wordplay.
'paying' becomes 'footing' (as in footing the bill).
'for' says to put letters next to each other.
'foundation coppers' becomes 'thebill' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'footing'+'thebill'='FOOTING THE BILL'

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I've seen this clue in the Sydney Morning Herald.

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