Spent about a pound for cloth (5)
I believe the answer is:
plaid
'for cloth' is the definition.
(plaid is a kind of cloth)
'spent about a pound' is the wordplay.
'spent' becomes 'paid' (I can't justify this - if you can you should give a lot more credence to this answer).
'about' is an insertion indicator.
'a pound' becomes 'L' (abbreviation e.g. Lsd - pounds, shillings, pence).
'paid' enclosing 'l' is 'PLAID'.
Can you help me to learn more?
(Other definitions for plaid that I've seen before include "Tartan-pattern cloth" , "Scottish Highland fabric" , "piece of cloth" , "Scots cloth - Welsh party" , "party in Wales" .)