Just a footnote on repair of spring wire(s)
I'm adding this for info, those that might follow this thread and still want to repair a broken spring. Mine ('85 380SE) had 2 broken spring wires. I removed the seat, turned it over, and inserted some aluminum flashing to protect the unholstery materials, then MIG welded the wires. Returned seat to car, and listened to both wires break on the first seating! I was told later that you can't Mig weld spring steel (wish I'd heard this first).
So, back to the shop, flip seat over again, this time I crimped some split tubing over the broken joints, with vise grips. The repair has lasted 6 months, seat feels fine now, as the padding wasn't badly worn. I did insert 2 coils from another seat into the corners, stuffed with HD foam, and this really firmed it all up nicely...
2002 Toyota Camry