sir atomicpandesal,
try mo po humanap sa authorized distributor ng jbl for the cone kit (cone, edge, spider, voice coil and adhesive) para sa JBL 140-8. We can assemble it for you. or if you want we'll search for a replacement cone and edge, similar to the original, we'll retain the original voice coil. Price depends but assure you, it will be very reasonable and sulit.
thanks,
Benedict