Rare Rear Filding Van Seat

One is thinking of a project. Like we do gearing up for lighter/more sunnier times ahead. I’m thinking folding van seats to fit to my Daihatsu Extol (2006). On the rear of my passenger and one maybe in the drivers Any genuine ones available? Is there such a thing? alternatively I’m thinking folding taxi seats? Duly acknowledge I will need seat belts and will need to inform insurance company.