That is definitely the oil pump gear! Order a nice aftermarket, higher volume gear while you're in there and read the manual while you're at it. There is also a pin that keeps that gear in place. You better find it! The gear on the back of the outer clutch basket needs to be looked at as well since that gear is fucked. Also, the gear on the back of the clutch basket comes off and is only meant to go on in one way. Be very cognizant of the gears and shim that come off once you start pulling that basket out. Holler if you have any questions.