It is 3.5 meters in diameter, and almost 8 meters long. The last Picture shows then engine gimbaled with Pitch@+13Deg and Yaw@+10 Deg. The AeroSpike nozzle was designed using "AeroRocket" (at http://www.aerorocket.com/MOC/MOC.html) tool.
Please be warned the attached CAD files are huge and takes a long time to load up.