Royal herald finds court card attending weaponry (4-2-4)

I believe the answer is:

king-at-arms

I'm a little stuck... Click here to teach me more about this clue!

'royal herald' is the definition.
'king at arms' can be an answer for 'herald' (thesaurus). I am not sure about the 'royal' bit.

'court card attending weaponry' is the wordplay.
'court card' becomes 'king' (king is a kind of court card).
'attending' becomes 'at' (e.g. at school means attending school).
'weaponry' becomes 'arms' (synonyms).
'king'+'at'+'arms'='KING-AT-ARMS'

'finds' acts as a link.

Can you help me to learn more?

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

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