Under $4k budget build LA360 build

Sounds like you are well on your way!
What your 3 things add up to is pretty much personal choice. What does your engine builder suggest? Carbs are pretty much a personal thing; I'm a Holley guy myself but to each his own. And a carb swap can be easily done if you're not happy with the results. What does your engine guy say about the TC and pistons?

The machinist I was talking to turned out be someone I wouldn’t trust to make any decisions for me. He’s a quality guy who works with stock setups and doesn’t dip into the performance world. The block was measured and is said to be ready for assembly. After I get the pistons sorted out, I’m going take it to another shop that was recommended to get the rotating assembly balanced and a final assessment on the block and get an accurate measurement of the heads combustion chambers... I did my own measurements(twice now) and got about 71cc’s, but I want to make sure. They’re going to Sonic check it and we’ll see what else they suggest. I trust the knowledge here on this site on piston choice and anything else MOPAR related, so I figured I’d have my setup dialed in as best as I can before going to the new machinist.