Case favoured Pennsylvania city beyond its state (9)

I believe the answer is:

papeterie

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'beyond its state' is the definition.
I can't judge whether this definition defines the answer.

'case favoured pennsylvania city' is the wordplay.
'case' becomes 'pa' (I am not sure about this - if you are sure you should believe this answer much more).
'favoured' becomes 'pet' (as in a pet project).
'pennsylvania city' becomes 'erie' (I've seen this in another clue).
'pa'+'pet'+'erie'='PAPETERIE'

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