I recently tested a mild 360 that went in a 66 Dart, the engine created 358 hp with no problem.
dual plane intake
650 edelbrock 800 made no more HP
mild cam lift in the 480's {don't remember specifics}
cast iron J heads with no extra work.
roller rockers
flat top pistons {approx. 9 to 1}
balanced rotating components
This was a fun engine to test!
sipped the premium pump gas and ran Smooooth.

According to the volumetric efficiently of this combo a set of heads {more flow} larger cam, more compression and the 800 carburetor {or larger} would be the next upgrades.
good luck on your build