Replace wifi chip/card, or USB wifi possible?

My wifi just DIED, as in started acting flakey, and then eventually just shows that it's not available. I'm sure it's HW because I'm a net admin and did everything possible testing my router, IP's, etc. This just doesn't pick up wifi at all.

Googling the problem, I find no teardown showing the wifi, or anyone who has successfully found a USB wifi replacement workaround.

I'd much rather replace the wifi card, but don't see it in the ifixit teardown either. Any chance you caught this and know where a guy can find a replacement or a work around?

Thanks! Just hate to toss a $600 tablet!