Part of breathing apparatus to display intact, reportedly (7)
I believe the answer is:
airhole
'part of breathing apparatus' is the definition.
'display intact reportedly' is the wordplay.
'display' becomes 'air' (I've seen this before**).
'intact' becomes 'whole' ('whole' can be similar in meaning to 'intact').
'reportedly' shows a homophone (sound like).
'whole' is a homophone of 'hole'.
'air'+'hole'='AIRHOLE'
'to' acts as a link.
(Other definitions for airhole that I've seen before include "vent" , "breather?" , "may avoid suffocation" .)