Another seat cover replacement

The burlap with wires in it serves a dual purpose. it keeps the batting from going through between the springs. The wires in it keep it flat so it doesn't go between the springs but also transmits forces from one spring to the next so they move together.
This means some of the springs beyond the width of your butt are being used too without having the skin alone spreading that load. Year One and others do offer that material.
Many upholstery shops will suggest a heavy home type carpet to replace the cross wired burlap. I almost went that route but... When I was at the wholesale fabric shop for muslin fabric I noticed burlap available in colors for cheap. So black burlap from them and a coil of electric fence wire from Lowes was all I needed to make my own.