Tom Morana (moranav6racing.com) offered a bunch of hp parts for the 3.0. His site is not currently working, and his social media page doesn't get updated very often, so not sure what the deal is.
The stock PCM might handle some low boost, but it's not going to do very well with it. The 3.0 likes to ping in stock form, so adding a bunch of boost and hoping that there's enough overhead in the injector tables to keep up seems like a bad idea.
You can get custom PCM tunes through a local tuner (many have used local SCT guys with good results) for under $500. That's cheap insurance compared to the cost/hassle of an engine rebuild or replacement.
Megasquirt or Microsquirt could be an option too for people with smaller budgets and more time/experience tuning.
My suggestion to anybody wanting more power from their 3.0 is always something like this:
1st priority- inexpensive, easy
-Throttle cable mod
- Make sure maintenance is up to date and no issues with engine condition
2nd priority- Cost increases a bit, but mostly bolt on parts that will have a noticeable effect
- Underdrive pulley
- Electric cooling fan conversion
- headers/exhaust
- Roller rockers (assuming Morana still sells them). I'd also add valve spring upgrades at this point as stock springs tend to float at higher rpm.
3rd priority- Most expensive and/or advanced but net biggest improvements
- Camshaft replacement
- Porting/polishing lower intake manifold and cylinder heads
- Adding boost. There have been a number of boosted Vulcan 3.0s over the years, both here and other corners of the internet. Stock bottom end is good for ~15lbs at least, but I've never read of anybody pushing enough boost to break one (provided they have a proper PCM tune). Ford was comfortable offering the Whipple kit with a warranty at 10psi, so that seems like a conservative boost level, and you can experiment from there.
You'll want to make sure you've got proper axle gearing for your goals as well.
For a pretty normal truck, and a person with a limited budget/ average wrenching skill level I'd probably just do the efan and underdrive pulley and be done. They'll free up some hp and improve fuel economy at the same time. Maybe add a cat back exhaust if you want to make it sound a bit more aggressive.