Penny submits additional business proposal for Charles Edward Stuart and Perkin Warbeck? (10)

I believe the answer is:

pretenders

'charles edward stuart and perkin warbeck?' is the definition.
(the men are two examples of pretenders)

'penny submits additional business proposal' is the wordplay.
'penny' becomes 'p'.
'submits additional business proposal' becomes 'retenders'.
'p'+'retenders'='PRETENDERS'

'for' is the link.

I've seen this clue in The Independent.

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