4.0L piston slap

I have an '05 Prerunner with almost 150k on the odo. I have noticed over the past year or so an unusual sound when it is first started up. I believe it is a piston slap. I dont know a whole lot about this condition, so I would like anyone's advise that has dealt with this before.
So my questions are:
1- Do i have to worry about this causing engine damage?
2- Are there any quality repair/rebuild engine kits I can look for?
3- Is there any way to possibly stroke a 4.0L without getting into too expensive of a build?
Thanks everyone.

 

to answer #3, yes but not cheap... Check out Torspd build.

 

Ok, so stroking my Taco might not be in the cards for now. Any suggestions on maybe a mild bore and piston size to go to so the slap problem is eliminated. I know factory tuned these things are around 245 HP, my goal is to get it in the neighborhood of 300 without breaking the bank, and staying N/A. I unfortunately don't have a 4X4, but I do want to do some off roading and feel like the 300hp range should work nicely.
Again, any advice is greatly appreciated. Since I have her paid off, and no longer have anyone telling me I can't do it, I want to build my Taco up to have fun off roading and camping with my kids.

 

If you are worried about it take it in to get it looked over.