Canbus stereo into non-canbus car?

[DuraAce]

Would like to install a canbus stereo in a non canbus car.

As I understand it the can bus stereo is supplied with permanent live (no switched ignition feed) , the car then signals the stereo on/off via a canbus signal as the cars ignition is switched on and off.

Does such an adapter exist as to provide the can h/l signal to turn the stereo on/off?
Or is there another way?

[Penelope Stopit]

You may find it more worthwhile in asking a specialist to modify the unit for ignition switching