Ok, I was able to glue the 2 pieces back together with Loctite Ultragel Control - wow. that stuff works great on whatever type of plastic these are made of. Then I re-attached it to the headlight using some Permatex Black Silicone Adhesive Sealant. I'll wait a day for the silicone to cure, then reinstall the headlight tomorrow.
You really can't tell it was cracked unless you are right on top of it.
I think I might just hold off for a while on ordering a new one... I've been thinking of adding headlight washers - maybe I can use this as an excuse to do that...
