Remember, there are two types of power adaptors from that era, a 45W and a 65W. The 12" PB likely takes a 65 W (but I'm not 100% sure that all 12" PB take that, I know mine takes 65W.)
I have an extra that I'm looking to get rid of, I'll ask $55 shipped as well when paying via Paypal, $50 when paying by money order or bank check. PM me if you (or anyone else) are interested....