It will be the metal framed seats that fold up lie down and turn round, early VW split screens had them, you will see the type of seats in Bedford Dormobiles.
A lot of Splitscreens that may have had them have had them removed by owners unaware of the rarity.
I remember seeing an episode of pimp my ride on MTV where an original Martin Walter splitscreen had its original interior, seats roof etc scrapped,the van ended up with some over the top impractical interior.
Regards
Malcolm