Replacing a crank shaft questions

you can also cut down a 360 crank for more piston availability and another 20 cu inches and 20 ft lbs of torque- which you can feel especially with an auto trans
if you just need a crank first do as YR says one score is not fatal especially in the center where there is an oil grove anyway
there are cranks out there
318 crank is going to like light pistons or else heavy metal to balance
Scat not Eagle if getting a kit
strokers also have more piston choices
saving a few bucks is a consideration and cast cranks are fine for a street build with an AT you are not going trans am racing
that said if you need pistons go light maybe even with a longer chevy rod makes a big difference on how the motor revs
and you are removing weight from the crank not adding
+ if you get a 318 crank and 318 weight 340 pistons you might not even have to balance
lots of way to skin a cat
you must have a great wife