Bang for buck though... Cam and tuner by far. Exhaust is always last job when building or tuning an engine. Big HP and an exhaust results in a loss of power.
Just trying to save the OP some dollars.
Raising the valve curtains and optimizing valve event timing by putting in a custom ground camshaft is the single most cost effective mod you can make for a bone stock motor. You can leave the stock exhaust alone on most motors too, and still get a considerable percentage increase in torque and tractible power below the rev limiter.
Why the camshaft? Because the camshaft controls the Dynamic compression ratio, increases Volumetric efficiency and greatly improves brake-specific fuel consumption (HP per pound of fuel consumed) which is a key indicator of overall engine fuel conversion-to-power efficiency.
Generated Cylinder pressures are what creates torque and power under the limiter. I'm talking about acceleration and power you can feel in the seat of your pants and actually put on the ground to do work. Way more bang for the buck than any other mod if done right!
The exhaust system is optimized last by the designer as Sam noted, because its job is to carry the volume of oxidized gases away to meet the demands of the gas exchange process defined by the physical constraints, the type of fuel, loads and RPMs of the motor. It is critical that the exhaust is designed well on a heavily modified motor.
Save your money... you'll need it soon for other routine repairs & maintenance on your Rancher. Honda don't make 'em like they used to...