I think... I think and correct me if I am wrong. You want an internal cam and mic... External would be just dangling from your PSP and could get quite complicated.
You want more space, so something like a PhotoFast CR-3100
Red LEDs in the triggers
And painted trim.
I am surprised you don't want a second analog stick. Just trying to organize your thoughts so people can understand them a bit better. The Cam and Mic are going to be the most expensive part of this mod. Even if you provide the parts the labor still is going to cost a bit. But I assure you it will be less that 1000$. Who knows maybe 998$. Kidding. >.<
-TwisT