Bottle stocked by finer vendors (5)
I believe the answer is:
nerve
'bottle' is the definition.
(both can mean courage)
'stocked by finer vendors' is the wordplay.
'stocked by' says the answer is hidden in the clue (the answer is contained or stocked by the clue).
'NERVE' is hidden in the letters of 'finer vendors'.
(Other definitions for nerve that I've seen before include "Courage to carry on" , "Steadiness, courage" , "Hold it and maintain courage" , "displaying self-possession" , "Impudence (colloq.)" .)