I bow to you guys/gals who do this for a living.... what a PITA to re-cover one seat. (just did the back one and looking for new seats for fronts)
I have used stainless tig welding wire to replace the wires in the burlap, get a size close to the original size and use the old wires as a pattern. Takes a lil bit of time but makes the seat nice. You will probably also find the outer seat side springs are broken on the seat bottom, you can get just the side springs from ground up or other suppliers for less than $20.00Hi RJ,
You should be able to get new burlap from your local upholstery shop = not expensive.
but it doesn't have the reinforcing wires in it.