Arm and leg finally received by Attila?
I believe the answer is:
handgun
'arm' is the definition.
(handgun is a kind of arm)
'and leg finally received by attila?' is the wordplay.
'finally' says to take the final letters.
'received by' indicates putting letters inside.
'attila?' becomes 'hun' (attila is a kind of Hun).
The final letter of 'leg' is 'g'.
'and'+'g'='andg'
'andg' placed into 'hun' is 'HANDGUN'.
(Other definitions for handgun that I've seen before include "potential killer" , "Eg, pistol" , "Pistol, perhaps" , "Revolver" , "piece" .)