I assume you're looking for a cable to connect an old USB Type-A port to the phone's Type-C port. I have a bunch of micro-usb cables lying around everywhere I might need to connect my phone to a computer, so I bought these adapters instead.

http://www.amazon.com/gp/product/B0191FRCAA

Kept one at my desk, tossed the other in my bag. They work fine, and they don't look like they'll break anytime soon.