Candidates for a quiet gripping instrument (8)

I believe the answer is:

appliers

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'candidates' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'a quiet gripping instrument' is the wordplay.
'quiet' becomes 'pp' (music symbol for 'pianissimo').
'gripping instrument' becomes 'liers' (I can't justify this - if you can you should believe this answer much more).
'a'+'pp'+'liers'='APPLIERS'

'for' is the link.

Can you help me to learn more?

(Another definition for appliers that I've seen is " used for spreading on glue etc".)

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

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