Which aluminum intake and carb to use?

With the 318, you can use virtually any dual plane manifold. The Edelbrock Performer RPM air gap intake is really good, maybe too good for the stock heads and small valve sizes. Find a good used Holley 600 cfm carb.
Don't expect a huge gain though, you can't get really big gains with those stock 318 heads. Your next mod should be a set of 340 or 360 heads and getting rid of those factory low compression dished pistons.