No way coffers filled with money in disused currency (8)

I believe the answer is:

ostmarks

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'filled with money in disused currency' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'no way coffers' is the wordplay.
'no' becomes 'O' (O resembles 0).
'way' becomes 'st' (abbreviation for street).
'coffers' becomes 'marks' (I can't justify this - if you can you should believe this answer much more).
'o'+'st'+'marks'='OSTMARKS'

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I've seen this clue in The Guardian.

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