Looking for compatible NON 6 disc radio with AUX button

[BLOWNZO6]

I am looking for a non 6 disc radio with the aux button for a factory external changer on it still.

I want something that is cheap and compatible with the onstar system and the factory speakers in the truck.. don't care what condition it is in as long as it works correctly.

Any ideas.. is there a NON changer head unit option for our trucks.. and if so anyone have one they would like to sell?

Need it for a cool project I am working on.. I will show all when it is done.. just need that for now.

TIA