Rely on advertisement for financial institution (10,4)

I believe the answer is:

commercial bank

'financial institution' is the definition.
(commercial bank is a kind of financial institution)

'rely on advertisement' is the wordplay.
'rely' becomes 'bank'.
'on' is a charade indicator (letters next to each other).
'advertisement' becomes 'commercial' (commercial is a kind of advertisement).
'bank' after 'commercial' is 'COMMERCIAL BANK'.

'for' is the link.

I've seen this clue in The Telegraph.

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