Reserve a coat for winter (5)

I believe the answer is:

parka

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'coat for winter' is the definition.
'parka' can be an answer for 'coat' (I've seen this before). I'm unsure of the 'for winter' bit.

'reserve a' is the wordplay.
'reserve' becomes 'park' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'park'+'a'='PARKA'

Can you help me to learn more?

(Other definitions for parka that I've seen before include "Short, hooded coat" , "Hooded weatherproof coat" , "outdoor clothing" , "weatherproof cover" , "Hooded waterproof coat" .)

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

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