I got that pic. off of their Japanese website (real hard to navigate when you know NO Japanese!). I make my own, but if you want one for a Novarossi, RC Rage I think makes them . They are $45 for the regular and $60 for the race version. I have used one of my own design for about a year now and it works great for on-road use, especially at top revs (gives a top-end rush feel to the powerband), but they suck for off-road unless you run dirt oval (where I mostly use mine). CMB Italia engines has been using this design in their .21 race engines for a while now, serpent just cuts scallops out of the backplate on the Novamega race .21's.
