Woah! I just did this this weekend, I have some sweet advice for you.
I cracked the cone on one of my Pioneers a few months ago. I almost junked it, but thought I'd give it a shot. I thought about it for a while, and did the repair, and it sounds as good as ever. I think you really have to follow what I say for this to work, but I know it will.
Okay. I had two cracks in the cone, one spread to the surround, and the other stayed in the cone. Step one was aligning the surround so the crack was even at the crack. then I flipped the sub over, on a towel, and mixed up some two-part epoxy, the type that dries hard. Mine was yellow. The important part is that the stuff bonds to plastics and dries very hard. Once it's mixed up, paint it on the crack on the backside of the sub. Paint it about an inch wide, I used a toothpick. Start it up by the voice coil, as the epoxy will want to run down the cone. DO NOT let it get to the surround. Apply it to the edge of the cone, up to the edge of the surround. Let it dry, and do a second coat. You should be fine now.
If the surround is ripped, too, I'd suggect using a glue that dries flexible. I'd normally recomment sillicone, but it eats away rubber surrounds. I used Goop, a marine glue, and it worked well and stayed flexible. I used one coat, to keep it flexible and because it is thicker than the epoxy.
I did this, and drove the sub hard, and it held up well. Keep in mind the TS-W303F is a free air cub, meaning it is not for enclosure use.
Good luck, I saved $65 by doing this, and I hope you do, too.
