Buckingham Palace insider, my good source of information (5)

I believe the answer is:

corgi

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'buckingham palace insider' is the definition.
I can't judge whether this definition defines the answer.

'my good source of information' is the wordplay.
'my' becomes 'cor' (both are expressions of surprise).
'source of' suggests taking the first letters.
'information' becomes 'i' (common abbreviation for information).
The initial letter of 'good' is 'g'.
'cor'+'g'+'i'='CORGI'

Can you help me to learn more?

(Other definitions for corgi that I've seen before include "Dog of Welsh breed, royal favourite" , "Royal canine" , "Queen's dog?" , "found in the kennels" , "Welsh breed of short-legged dog" .)

I've seen this clue in The Telegraph.

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