I don't know of any turbo kits made for these cars, but 200hp on L-Jet isn't a problem, you will have to make some minor modifications, but nothing drastic. I have seen 200rwhp with L-Jet on a forced induction 2.5.
Upgrades to the motor while it's apart are a good idea, but not required. I like to use forged pistons. For one thing they can be non-interference, and considering how crappy our timing belt tensioners are, that's good insurance. Obviously forgies are stronger too. That's about all I usually do, sometimes I use better rods.
Greg