I cant find a replacement charging assembly? Do they still make them?

You do not need to find a specific Pixel charger. Any android phone I have ever seen for the last 10 years or so has a USB charging port. I am sure the Pixel does. It is probably a USB Micro port but might be a USB C port. Thousands of chargers have a USB A port on the adapter allowing you to connect a USB A to USB Mini or USB A to USB Micro or USB A to USB C cable. The other thousands have an attached cable with one of those USB connectors.

To charge as efficiently as the original, the adapter must have the same or higher current rating and if the phone has QC capability, the same or higher QC rating.