Looking for a little more power out of a 318

http://www.moparmusclemagazine.com/techarticles/mopp_0409_318_engine_build/index.html

Heres a good article for 400+

I like the teen myself. You have a fresh rebuild, and to me thats the problem, who did the rebuild? stock rebuild with something other then a stock cam seems a little fishy to me. I think you stated that you dont know the specs of the cam. I think thats a problem, without knowing that its hard to figure out what "add ons" you should do.
Is the motor in the car and running? If its not in the car, do what you want to it. my suggestions would be

Comp xe 262-268. To be honest you wont tell the difference and the 262 will hold a little more torque

Intake- This is where you need to decide how much money you want to put in and how far you want to go.
little money- Eddy preformer
more money-Airgap........but, with the air gap you need to upgrade other things, like heads and carb. so make the dicision first. Heres my favorite build

318- bored .30
KB167 pistons
596 heads, the smaller 1.88 valves, not 2.02 you still need the velocity
Air gap
600-750 carb
XE262 or 268 cam with 901 springs
mopar thin head gasket. This brings you to zero deck without haveing the deck squared.
Eagle I beam rods