RE: throttle gear
all you can do for the moment is replace it with another cheap gear 'cause its all there is right now. But. you can adjust the position of the engine better so that the clutch bell is not too clos neither too far from the central gear. It is normal for those gears to strip after awhile but not that soon. the reason why yours stripped is probably the alignment. search the threads, you will find alot of info about this issue...