Building a 340 engine

Welcome! Sounds like fun and we love pictures here!
How about some flat top Icon forged pistons?
Cam seems very mild. Look up a stock 340 cam and jump one level of duration higher.
I used a Crane 427/454 cam in a truck with 4.10 gears and 28" tires. Did not notice it at idle,vacuum was good and pulled well.
But I'm sure your car does not weigh 4500 lbs!
Good luck with the project!