Welcome, 0120raptor!
Mraxl has some oil recommendations on the resource site:
http://kawatriple.com/faq.htm I just use whatever TC-W3 is cheap and have never had a lubrication problem, and that goes back to 1978 with my H2, when I ran Kawasaki K1 in this same engine. The dealer used to have a good price on a full case of 1 quart bottles.
I run 93 octane (R+M)/2 pump gas without any problems. If I'm not going to ride much I try to leave it with no-alcohol gasoline in it, but many times I didn't bother. I do store my H2 in a heated and air conditioned garage, so it doesn't get moisture condensing in the tank.
Our 93 R+M/2 is about the same as the UK's 98 RON, so I run about what you plan to.