Day coats unfashionable in dyed sheepskin (6)

I believe the answer is:

mouton

'dyed sheepskin' is the definition.
(sheepskin dyed to resemble fur)

'day coats unfashionable' is the wordplay.
'day' becomes 'mon' (abbreviation for Monday).
'coats' means one lot of letters goes inside another.
'unfashionable' becomes 'out' (synonyms).
'mon' enclosing 'out' is 'MOUTON'.

'in' acts as a link.

I've seen this clue in The Times.

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