Fine - a thousand pounds (5)
I believe the answer is:
grand
This clue is a double definition.
'fine' is the first definition.
(I've seen this before)
'a thousand pounds' is the second definition.
(slang)
(Other definitions for grand that I've seen before include "Type of piano" , "Large and imposing" , "Designed to impress" , "Impressive, large" , "Fine" .)