Searching for a Harman Kardon subwoofer.

Hello. Recently i bought a 2cnd hand 2015 Challanger SRT Hellcat. It was a salvaged title, that I decided to fix up. The car is done now, but while transporting the car, someone stole the subwoofer from the back, since it had rear end damage and the trunk couldn't close. Now i've been searching for a new sub, but i can't find one with all the plastic housing. Anyone have any ideas where i can find one?