Opinions on 318 Needed

My opinion, look for an inexpensive 360/727 combo with low mileage. A stock 318 will give you a little more HP than your slant 6, but a 360 will give you more to work with down the road.

and requires less hi-po goodies for the same output.
And if you find a complete pkg, including things like the KD mech,the dizzy,carb, the mounts,etc; up here it might be worth 2 or 3 times that,even as a core. I have bought semi-complete donor cars to get what I need, for $250 to $350 . Bring your own wheels!