East German comes in ready to make reply (7)
I believe the answer is:
riposte
'reply' is the definition.
(riposte is a kind of reply)
'east german comes in ready' is the wordplay.
'east german' becomes 'ost' ('east' in German).
'comes in' indicates putting letters inside.
'ready' becomes 'ripe' ('ripe' can be similar in meaning to 'ready').
'ost' put inside 'ripe' is 'RIPOSTE'.
'to make' is the link.
(Other definitions for riposte that I've seen before include "Smart reply" , "Rejoinder" , "Reply, retort" , "Quick and witty reply" , "Sharp answer" .)