How to draw another camera's view without "Handles"-class?

I can't seem to find a working answer...

I want to draw another camera on top of a GUI element without using the Handles class. Because the Handles class is an editor-only class. So I can't export my game then. Is there a good solution? The cam's Rect is:

 Rect(Screen.width-170,Screen.height-153,123,109)

Whole code for the camera drawing:

 Handles.DrawCamera(Rect(Screen.width-170,Screen.height-153,123,109),BirdCam,DrawCameraMode.Normal);