(2)When an imported firearm kept for sale by a dealer does not bear the manufacturer's name, such distinguishing mark of the importer as allotted by the State Government shall be engraved on the barrel and the frame, or the barrel and the receiver of the firearm after obtaining prior permission of the licensing authority:Provided that if a barrel bears more than one number, the distinguishing mark shall be affixed to the number appearing on the original invoice:Provided further that where the manufacturer's number appears only on the trigger-guard or other replaceable part, that number shall also be engraved on the barrel and the frame, or the barrel and the receiver of the firearm.
