I would go the route of a good sounding exhaust system because that 270H cam with say a 40 or 50 series Flowmaster (not that I am stumping for Flowmaster but they're my preference) exhaust system should sound anything but stock. I put the 270H in my '67 Chevelle SS 396 when I rebuilt the engine. I had the 50 series (non-Delta Flow) mufflers WITH 2.5 " exhaust and 3.0" tailpipes mounted to Hooker Competition headers. I ran the Turbo 400 trans with shift kit and 2800 stall converter. That cam gave me all the power I needed and it had a great sounding lope to go along with the performance. Stick with the 270H, especially if you are running an automatic transmission.
That's my nickels worth...
Greg