To my knowledge, all you would need would be, motor, mounts, tranny, probably driveshaft(not sure of the camaro's tranny difference from 6 to 8), rearend, front suspension parts(stronger springs may be all you need, not sure). If the trannies are significantly different, then you may need to do some clutch(if manual) changes. This would be fairly simple if you are automotively inclined, and have a V8 parts car sitting right next to the sixer. I can't think of anything, but will post if I do. Good luck, sounds like a good project.
Edit: Sorry, I just realized that you were asking about the cost of the project, and I didn't answer that at all
. I am not up on what 3rd generation V8 F-bodies are going for, but whatever it is, expect a significantly less amount for a parts car with just good working mechanicals. I am going to guess around 1000??? Sorry if this is totally off, but that is just my guess for a wrecked, but salvageable car. Now you have to take into account the reconditioning of some of these parts which could add up if you don't shop around
. I will make an extremely rough guesstimation of about $3000 total? These other guys can probably help you more than I can on that.