The rest cure as organised accumulated wealth (8,5)

I believe the answer is:

treasure chest

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'accumulated wealth' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.

'the rest cure as organised' is the wordplay.
'organised' indicates an anagram.
'the'+'rest'+'cure'+'as'='therestcureas'
'therestcureas' is an anagram of 'TREASURE-CHEST'.

Can you help me to learn more?

(Other definitions for treasure chest that I've seen before include "Source of riches" , "Valuable container" , "Box containing gold etc" , "Box of riches" , "Typical pirate hoard" .)

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

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