Article by bad penny, say, intended for mass market (3-3-3)
I believe the answer is:
off-the-peg
'intended for mass market' is the definition.
'article by bad penny' is the wordplay.
'article' becomes 'the' (the 'definite article' part of speech).
'by' is a charade indicator (letters next to each other).
'bad' becomes 'off' (I've seen this before).
'penny' becomes 'peg' (I can't justify this - if you can you should give a lot more credence to this answer).
'the' after 'off' is 'offthe'.
'offthe'+'peg'='OFF-THE-PEG'
'say' acts as a link.
(Other definitions for off-the-peg that I've seen before include "(Of clothes) ready-to-wear" , "Of clothes, not made to measure, on the rack" , "Not made-to-measure" , "Of clothes, bought ready to wear" , "Of clothes, bought ready-made" .)