Seadoo Hx, impeller repair, and other tips?

So, im getting started with the jetski hobby, and bought a seadoo hx -96. Its impeller is damaged, and needs to be replaced. Im going to do that now, before the jetski season starts. I have the shop manual from skidoo, and have read it to get the idea what am i going to have to do. I have decided to overhaul/repair the impeller unit at the same time.

Im posting here, because i need some tips, and advices before i start doing the repair.

I was looking for parts needed for the repairs, and found lots of jet pump repair kits, with seals and bearings. Allso noticed, that there are lots of aftermarket impellers on the market, can anyone tell witch one would be good to buy, or the OEM? And if someone of them is better than other, id like to know why? Im willing to sell little bit of top end speed, to acceleration. Engine itself has no mods in it.

It would be nice, if you could tell me what i need to buy to get the repair done, seal rings etc.? And it would be great to get them on one shop, and cheap. One shop option is because i live in Finland, and could get all of the parts on one delivery costs, and taxes here.

Allso all tips and advices about the jet, and its maintenance or its major faults would be great to know, so i can get it fixed before summer.

In the watertunnel before the impeller, there is some of the paint left of for some reason, any tips how to fix?

At the same order, a friend of mine would like to get new impeller for his jet too, its yamaha waverunner 1200 -98. He is looking for more top end speed. If you can recommend what impeller is good for him, so i can get it coming here with the same order where are my parts going to come.