So-called Special Force open to literary award (6,5)

I believe the answer is:

stella prize

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'so-called special force open' is the definition.
The definition suggests a verb in its base form which matches the answer.

'literary award' is the wordplay.
'literary' becomes 'stella' (I can't explain this - if you can you should give a lot more credence to this answer).
'award' becomes 'prize' (synonyms).
'stella'+'prize'='STELLA PRIZE'

'to' acts as a link.

Can you help me to learn more?

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

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