Son, sober perhaps, up for some cheese (7)
I believe the answer is:
stilton
'some cheese' is the definition.
(stilton is a cheese)
'son sober perhaps up for' is the wordplay.
I cannot quite see how this works, but
'son' could be 's' (genealogical abbreviation for son) and 's' is found within the answer.
'for' could be 'to' (eg both can mean 'in the opinion of') and 'to' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for stilton that I've seen before include "Strong English cheese, originally from Leicestershire" , "Strong Eng. cheese" , "No tilts (anag.)" , "Rich, blue-veined cheese" , "Lost tin (anag)" .)