Stickler's point in trading centre (8)
I believe the answer is:
martinet
'stickler's' is the definition.
(I've seen this before)
'point in trading centre' is the wordplay.
'point' becomes 'tine' (I've seen this in other clues).
'in' means one lot of letters goes inside another.
'trading centre' becomes 'mart' (I've seen this before).
'tine' inserted inside 'mart' is 'MARTINET'.
(Other definitions for martinet that I've seen before include "Strict disciplinarian - met train (anag)" , "Rigorous figure" , "Despot" , "Tyrant, one who demands strict obedience" , "A strict disciplarian" .)