Possibly save about £1 for a bag (6)
I believe the answer is:
valise
'for a bag' is the definition.
(valise is a kind of bag)
'possibly save about ps1' is the wordplay.
'possibly' indicates an anagram.
'about' means one lot of letters goes inside another.
'psl' becomes 'li' (I can't explain this - if you can you should believe this answer much more).
'save' with letters rearranged gives 'vase'.
'vase' placed around 'li' is 'VALISE'.
Can you help me to learn more?
(Other definitions for valise that I've seen before include "Small piece of luggage" , "Small overnight bag" , "Travel bag" , "Small travelling bag or suitcase" , "A small suitcase for Leavis" .)