Someone earlier said that Specialized warrantied a frame for the non-original buyer. Assuming the blow-off stands why don't you give that a try? The worst that happens is you get told "no." Hell, I hear that from my kids all the time. Doesn't hurt a bit.

Then it's time to go the Nasbar route.

Best case is you end up with a new frame and after a convoluted route you got a nice deal for the $350.

I definitely join the chorus about not riding it unless you go the TIG weld repair. I have no idea how that compares to the Nashbar frame monetarily.

Good luck.