I found this car stereo that supports Miracast. It also has it's own GPS but Google Maps is better if you have a data connection at your location.
Eonon M2 with Miracast| Car GPS | Car DVD GPS | 2 Din Car GPS DVD | In Car DVD | Best Car GPS
Eonon M2 with Miracast| Car GPS | Car DVD GPS | 2 Din Car GPS DVD | In Car DVD | Best Car GPS