Recommendation needed

[79 Camaro]

So on your first post you said 2500. So I will change my mind somewhat. The 5.3 is OK but not a torque monster. Intake and exhaust will help but a good intake and exhaust is going to cost? Intake I'm guessing $300? Exhaust again guessing if aftermarket cat back $800? So $1100 for 20 hp? No disrespect but that's kind of expensive dollar per hp.
So my .02.
It's a tough call. But if you decide on a cam it will most certainly need better springs and push rods. At 250000 miles new lifters would be a good idea or at least a trunion upgrade. Run a compression check to check rings. So then since you need to pull the heads to replace the lifters a valve job? Also update the oil pump is always good idea. Not sure about cam bearings but if needed you are really talking about a total engine tear down. Again my way forward would be if the cash is available buy a 250000 5.3 that would plug into the truck. Rebuild it with good parts and drive it another 250000 miles.