When goods are sold out (6,4)

'sold out' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'when goods are' is the wordplay.
I cannot really see how this works, but
'when' could be 'e' (I've seen this in other clues) and 'e' is found within the answer.
'are' could be 'a' (short for 'are', historical unit of measurement) and 'a' is located in the answer.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?