best head for 318 street car

Your not rebuilding the engine are you?

If your going to meep the stock heads and do the a I've work, you'll need to know where the piston sits in the hole and the cc amount of the heads when all is said and done with them. M owing the flow numbers help but are not a must though a great addition to actually know. This with the head gasket thickness to be used will give you your compression ratio.

In a 50/50 driver setting, the cam you choose can be a little conserveitive for help in mileage and street manors or a little aggressive for more power with little care on mileage.
The difference is t so large as to worry.

Here is a cam that can do 14's in your set up without issue and idle smooth.
Crane cams 272/284 (216/228 @.050) .454-.480-112 IIRC, this cams power range is from 12 or 1500-5500 RPM's. no need for a converter change.

You can pick up a little more power with the Comp cam equal with less centerline for more of a chop at idle, the Lunati equal has more lift adding a few more HP.
All perform in the same ball park.

Going a more aggressive route, add 10*'s to 12*'s duration to each side of the split cam. This will still be a good driver, in a drivers range that should not have the wife complaining.