Models, casuals - late in (9)

I believe the answer is:

templates

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'models' is the definition.
(template is a kind of model)

'casuals late in' is the wordplay.
'casuals' becomes 'temps' (I am not sure about this - if you are sure you should believe this answer much more).
'in' indicates putting letters inside.
'temps' placed around 'late' is 'TEMPLATES'.

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I've seen this clue in the Sydney Morning Herald.

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