Anker A1229 PowerCore Slim 10000 Charger (USB-C Input Only) $15 at Amazon
Amazon with AnkerDirect has the Anker A1229 PowerCore Slim 10000 Portable Charger (USB-C Input Only) for $22 - 30% off coupon (check "Apply coupon" box) =
$15 with free shipping on $25+ or with Prime.
Original Source of Info