Impeller damage

[Doctor_Venkman]

While riding a couple of weeks ago, my brother managed to get get some serious rocks jammed in the impeller. So solidly stuck that it locked up the drive shaft and killed the engine. This is for my 2017 GTI SE (small engine)





So I've got a couple of questions...

#1 - I'm sure that I need to replace the impeller. Should I just get an OEM impeller or would there be any real improvement (top speed and acceleration) for this model with going with a more aggressive impeller? (Top speed is around 40 mph)

#2 - I need a removal tool and I've looked at several different shops online but I can't find one that clearly states my year & model. I need help finding one. (I would also buy one that fits my 2018 GTR 230 if different than the one for the GTI)

 

[Doctor_Venkman]

Just found out there was a considerable amount of water inside the cone. Should I be worried about that having caused more problems? Do I need new seals? I know I should clean out that area remove the old grease, etc. What type of grease should I put back in and how much?