eBay with vipoutlet has the open box Apple USB-C Digital AV Multiport Adapter (MUF82AM/A) on sale for $23 with free shipping. Adapter includes HDMI, USB-C, and USB-A ports. 

Seller notes on condition: Like New & Fully Functional condition however the product may have been taken out of the packaging and tested or the outer packaging may show little signs of scuffs, dents or may have also been repackaged.