USB Type-C cables can get pretty expensive, but if you don't need the fast transfer speeds of USB 3.0/3.1, Amazon's own AmazonBasics cables are a good option. In fact, they're an even better option right now, because they're on sale. Now you can get the 9ft Type C cable for $7.99 (20%) and the 6ft for $6.79 ($15% off).
As mentioned above, these cables are limited to USB 2.0 for data speeds, but they do provide a power supply of 5V/3A - making them perfect for quickly charging Nexus and Pixel phones. And before you ask, these are Benson-approved.
It's worth mentioning that only the white cables seem to be discounted, and not the black ones. You can find them at the link below.