The Factory Air Filter for the 1987 and 1988 Super Magnas was discontinued by Honda many years ago.  

This filter is from my private inventory and is still new in the sealed factory wrapping.  It is a direct fit for the 1987 and 1988 Super Magnas.

I've been restoring Supers and shipping parts for Supers all over the world for over 25 years.  If there's anything you need for a Super, feel free to contact me.