Unsentimental type about a set of items (7)
I believe the answer is:
realist
'unsentimental' is the definition.
(thesaurus)
'about a set of items' is the wordplay.
'about' becomes 'rea' (I've seen this in other clues).
'a set of items' becomes 'list' (I can't explain this - if you can you should give a lot more credence to this answer).
'rea'+'list'='REALIST'
'type' is the link.
This may not be correct. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for realist that I've seen before include "no Walter Mitty?" , "Writer like Balzac" , "Someone who's pragmatic" , "Is alert (anag)" , "Sensible man" .)