Girl in a thousand for instance (3)

I believe the answer is:

meg

'girl' is the definition.

'thousand for instance' is the wordplay.
'thousand' becomes 'm' (Roman numeral for a thousand).
'for instance' becomes 'eg' (short for 'exempli gratia', 'for example' in Latin).
'm'+'eg'='MEG'

'in a' is the link.

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

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