Crank is shot, do I stroke it or not?

OP has a lot of parts that would already work on either build.

He already has a 360 flywheel, that's the direction I would likely go.

new bolts and resize is pretty close to a new set of rods that a bunch lighter.

Figure out the true budget and work from there. A lot of this stuff will cancel out going either direction, crank vs crank, piston v piston, etc.

The 268 is going to be a puppy dog in a 408" engine.