Found a job for, though old (4)

I believe the answer is:

used

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'old' is the definition.
(as in used or second-hand items)

I cannot understand how the remainder of the clue works.

(Other definitions for used that I've seen before include "Accustomed, having been put into service" , "Dog-eared" , "Took advantage of" , "Second-hand; consumed" , "was milking" .)

I've seen this clue in the Evening Standard.

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