Or you can make one yourself. I don't have a photo but here is what I did:
Bought a 90 exhaust elbow at an auto parts store, making sure that one end of it would fit over the exhaust pipe of the rig. Bought a length 4" white plastic pipe. Drilled a couple of holes a few inches in from one end, attached a couple of stainless bolts in the holes, the bolts being inside the pipe. Notched the other end of the elbow. Push the elbow onto the exhaust pipe, notched end up. Placed the plastic pipe over the elbow with the bolts in the notches to hold it in place. I cut the pipe into two sections so it would fit in the basement storage bins. I used to attach the pipe to the side of the rig using bungee cords and suction cups but on this rig just leaning it on the roof edge and the mirror it is stable enough. Make sure the pipe clears the roof line and isn't too close the the air intake of the AC. You should also support the genies exhaust pipe to the ground to take the weight of it.