You live in california so your only choice would be the ford E cam. Unless you have a smog hookup. A smog station can fail you if they believe you have a non stock cam.
Yep. Unless they are trying to sell you a cam, any knowledgeable cam grinder will tell you the stock 5.0 HO cam is actually pretty stout. I've seen several builds making 350-400 crank HP use the stock cam. Of course, once you make those kind of numbers, a hotter cam would be a good idea.