Certain amount in bank gets right contractor (9)

'contractor' is the definition.
Both the definition and answer are singular nouns.
Perhaps they are linked in a way I don't understand?

'certain amount in bank gets right' is the wordplay.
I cannot really understand how this works, but
'amount' could be 'ten' (ten is a kind of amount) and 'ten' is found within the answer.
'right' could be 'r' (common abbreviation) and 'r' is found in the answer.
The remaining letters 'shoer' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).

Can you help me to learn more?