Luckily, I stumbled across a set of Austin Healy Bugeye seats. They had the adjustable tracks on them and the backs flipped forward for storage purposes. Believe it or not, they were actually comfortable as well.
They needed to be build up off of the floor a bit, so I had to make some mounts. This also allowed the driver's seat to clear the battery with sufficient room. I kept the front of the passenger seat open for storage.
I plan on adding a bit of cushion to the base and a small pad for the back. I really like these seats. I did make some templates for future projects in case I needed to make a couple.