I'm sure these topics have been beaten to death, but I'm having trouble finding what I'm looking for.

First, I own a jet boat, and not a PWC (yet, I am shopping for one). 07 Challenger 180SE w/ the 215 SCIC....so, pretty similar setup.

I bought her back in April with 48 hours, currently sitting at 73 hours. I've been noticing bad cavitation out of the hole, which looks like I've probably got a wear ring problem. I've eyeballed the impeller, and I see some damage to the fins. So, I'm assuming the original owner liked to beach this thing alot and throw sand through it.

My question is - what all do I need (besides the OEM wear ring) to perform this task? I've seen a couple different mentions of a gasket and some grease.

My other question - what would you recommend for an impeller upgrade? I'm topping out at 40mph (and about 7700rpm) right now, which I feel is real low. I've got 2 buddies with doo's....one a 2011 155 Speedster, and another with a 2012 210SE w/dual 215's, and they both run circles around me. Expected of the 210, but not so much the 155. I'm also planning on sending my SC in (for maintenance, not because I think that's the problem).

Thanks in advance (and sorry I didn't search more, I'm sure it's buried in here somewhere),