The charger is not covered by insurance. The insurance policy is for damaged or stolen Chromebooks. If the charger is lost or damaged it will be treated like any other school property (ie. textbook). The student/parent will be responsible for replacement.
1. Dell Chromebook 11 3100 (45-watt USB - C charger)
2. HP x360 Chromebook charger
Amazon - option 1
Amazon - option 2
Amazon - option 3
Amazon - option 4
All of these options output 45 Watts / 3.0A with a USB-C connection and state that they are compatible with the HP x360 Chromebook.
Please note that these recommendations are not guaranteed, they just have matching criteria.