Organisations like AA finance radicals (7,6)

I believe the answer is:

support groups

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'organisations' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'aa finance radicals' is the wordplay.
'aa finance' becomes 'support' (I can't explain this - if you can you should give a lot more credence to this answer).
'radicals' becomes 'groups' ('group' can be a synonym of 'radical').
'support'+'groups'='SUPPORT GROUPS'

'like' is the link.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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