Heres one, kind of expensive though. It has been 'one balled' though meaning it would fit straight away (removes the box at the left leaving only the one at the right). Whereas if you were to buy a stock one you would need to do this yourself. Not 100% sure though just remember as i was looking into this a while back, the pros will be here soon
Sidenote- hows your son gettin on with the drivin, aint seen his car kicking about yet