Dealer in the docks supplies cocaine to spy's boss (8)

I believe the answer is:

chandler

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'dealer' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for chandler that I've seen before include "Dealer, especially in ship's supplies" , "Dealer in soap" , "Dealer supplying shipment" , "supplying the goods in marine setting?" , "Author of Philip Marlowe thrillers, d.1959" .)

I've seen this clue in The Irish Times and the Irish Times (Crosaire).

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