Amazon with Solodream US Store has the ESR 2-in-1 USB-C to 3.5mm Headphone Jack Adapter (Dark Grey) on sale for $11.99 - 50% off with coupon code 5XO6F3XL in cart = $5.99 with free shipping on $35+ or with Prime.

Designed to support pass through USB-C charging (no data transfer) and wired headphone listening via 3.5mm port.