https://www.harborfreight.com/plastic-welding-kit-with-adjustable-temperature-96464.html

Plastic welding could work but may embrittle the plastic.

The 5200 would hold but I would drill the ends of the crack with an 1/8” bit to stop it from growing then clean it with alcohol or a wax remover before applying a bead and spreading it evenly across the crack. Let it cure completely before use. If you do this to both sides it will hold.