pipe & silencer, airbox lid removal, & jetting is a quick-n-easy power gain for ~$200.
Porting & right-bend would be nice, but if you're gonna go that route and she's stock.....gonna need to rebuild that motor top to bottom and to get the most out of it you'll need a bigger carb......which may lead to more airbox mods etc.
So it depends an how far you want to go with you motor. Just keep in mind a fast motor and garbage suspension and tires aint gonna work either. So if you want to get the most out of your 5 hundy and she's all stock right now, I'd do the $200 pipe deal I mentioned above and spend the rest on suspension and/or tires.