I want to have some seats at the front of the bus for passengers to ride comfortably and safely while we are going down the road. I think these Honda Odyssey seats will fit the bill. They have integral seatbelts and shoulder harnesses too, which will be a big advantage. I think these were available from 2016 on. I have seen them is wrecking yards for about $400 apiece.
I am also thinking about trying to fit one of these seats to an air ride base for use as a driver seat. Of course, you would have to be able to make them go to a fully upright position, because you sure don't want to be reclining while you're driving.