If I understand it correctly, it's only a 2 speaker system.
Stereo speaker computer cords can be found everywhere!
3.5mm audio cable. (stereo has 3 contacts)

Here's a couple Best Buy items,
Dynex 3 Audio Cable Gray

Insignia 3 3 5mm to 3 5mm Stereo Audio Cable Sea Green

Aux cable/cord should work. Most stores carry them or get it cheap on amazon.

Hi. Ir's a 3.5mm to 3.5mm male to male jack lead. They can be had on Amazon or ebay etc.

AKORD 3 3 5 mm to 3 5 mm Gold Plated Stereo Jack to Jack Lead Cable

Ok so you need a a/v cable to ear phone jack looking for one for u now.