Sunak's department relocated at Surrey (8)

I believe the answer is:

treasury

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'sunak's department' is the definition.
I can't tell whether this definition defines the answer.

'relocated at surrey' is the wordplay.
'relocated' is an anagram indicator.
'at'+'surrey'='atsurrey'
'atsurrey' is an anagram of 'TREASURY'.

Can you help me to learn more?

(Other definitions for treasury that I've seen before include "Repository of government funds" , "Exchequer - store for valuables" , "Its valued contents" , "The funds available to government" , "Finance ministry" .)

I've seen this clue in The Sun.

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