Leaf Spring info/help?

Yup. And on a car that's raced, the passenger side is the side that gets the most wear.
A thickmain leaf and good support at the eye from the second leaf is important in a car that will be run in the quarter mile, even without drag slicks.

The SS leaf package is designed for maximum traction when launching the car. For left right handling its not the way to go. Although for the Green Brick they had set dearched and it worked well.

For the OP. A good, preferably American made, leaf pack set can be had from various venders, possibly even a local spring shop.

Stengel Bros is PA but they will ship. I'd suggest picking the leaf set for the car you're building. If its a 383 car, then get the springs for a 383.
Dodge Lancer, Dart and Swinger Leaf Springs