Save a ship and rescue about fifty (5)

I believe the answer is:

salve

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'save a ship' is the definition.
'salve' can be an answer for 'save' (synonyms). I'm not sure about the 'a ship' bit.

'rescue about fifty' is the wordplay.
'rescue' becomes 'save' (saving is a kind of rescuing).
'about' indicates putting letters inside.
'fifty' becomes 'L' (Roman numeral).
'save' placed around 'l' is 'SALVE'.

'and' acts as a link.

Can you help me to learn more?

(Other definitions for salve that I've seen before include "Unguent" , "Skin ointment" , "Balm - ointment" , "Soother" , "Greeting in Rome" .)

I've seen this clue in The Irish Independent and The Globe and Mail.

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