Run off with gold in Pacific island? (5)
I believe the answer is:
nauru
'pacific island?' is the definition.
(I've seen this before)
'run off with gold' is the wordplay.
'off' is an anagram indicator.
'with' is an insertion indicator.
'gold' becomes 'Au' (Au is the chemical symbol for gold).
'run' with letters rearranged gives 'nru'.
'nru' going around 'au' is 'NAURU'.
'in' acts as a link.
(Other definitions for nauru that I've seen before include "SW Pacific republic" , "Pacific coral island republic, once rich in phosphates" , "little nation" , "Fairground carousel" , "[OCEANIA] location" .)