Salesperson always turned up carrying one spare (8)
I believe the answer is:
reprieve
'spare' is the definition.
(thesaurus)
'salesperson always turned up carrying one' is the wordplay.
'salesperson' becomes 'rep' (I've seen this before).
'always' becomes 'ever' ('ever' can be a synonym of 'always'**).
'turned up' is a reversal indicator.
'carrying' is an insertion indicator.
'one' becomes 'i' (Roman numeral).
'ever' written backwards gives 'reve'.
'reve' going around 'i' is 'rieve'.
'rep'+'rieve'='REPRIEVE'
(Other definitions for reprieve that I've seen before include "Punishment cancellation" , "Postponement as of death penalty" , "Give stay of execution to" , "Forgive" , "cancellation of death warrant" .)