I have got the ex BAS, nowadays http://lakevueaeronautics.com/_wsn/page2.html
foldable seats in my Skylane. They are by the way at least as comfortable as the original bench, and a LOT lighter.
I am really interested to do the same mod in my PA30, and am looking for other interested owners perhaps to do a group buy and/or share some cost for the DER drawings. This is a major weight saving and at the same time greatly enhances the utility of our aircraft.
Let me know if you are interested.
Robert