Run out of stock? (8)

I believe the answer is:

stampede

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

I can't explain the remainder of the clue.

(Other definitions for stampede that I've seen before include "Crazy pets made a sudden rush" , "Sudden mad rush" , "Sudden dash of a group of startled animals" , "Sudden rush of a panicstricken herd" , "unstable flight" .)

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

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