what cam for 340 bored 0.30 over?

Yea, oh yea!

What number TQ?
What are the valve sizes of the 360 heads being rebuilt?
What is your gear ratio and tire size?
Have you owned and driven a 340 car before?
Do you have power brakes?
Is a upgraded torque converter OK to spend on? They are pricey and you mentioned a 4spd swap.
How soon until you swap to a manual trans?

2500 stall TQ
Stock valve size. The 1.88 1.66 heads
Do you recommend milling of the heads to give me more compression?
Gear ratio: I don't know yet. Assuming it's in the 2.96s
Never owned or driven a 340 this is my first.
Future tire size will be 2457014
No power brakes
The manual trans swap won’t happen anytime soon. Maybe in a year or so. When that time comes I’ll look at where they engine stands and I’ll probably be back for more advice.