I have a set of very rare Volvo S90 Royal rear seat for sale, fits 940, 960 & S90 sedan, asking $350.
These are very different to normal 940 & 960 rear seats in many ways. Unlike the normal seats which has a large block of foam underneath, Royal rear seat has springs mounted on a wooden board, and they're electrically heated, providing exceptional level of comfort that's only found on Rolls Royce & the like. Royal seat also has leather all round including the sides, unlike normal 940 & 960 seats which are only leather on the seating face, with vinyl on the sides.
They came from a S90 Royal which I wrecked a year ago. Unfortunately a can of emergency tyre puncture repair kit exploded on the front passenger seat, covering most of the interior with adhesive. Some did end up on the back seat which is the only blemish, otherwise the leather is still very soft & smells like new.