We "solved" that delemma for a local with HIS '67 Camaro. He wanted just what was described. A little more power than the 327, better fuel mileage and still LOOK "correct". Well, he dynoed 276 RWHP (about 320 FWHP) and gets 17 MPG (or so he SAYS. I have no reason to doubt him).
We used mostly the same "stuff" you list on the outside, including the intake. What we did "different" was make a 355... Some '67s had large journals, some small. Which is yours? If "large", a 350 or 383 crank is a "drop in" deal, using 350 or 383 pistons. We've also ground the mains down to small journal and used a 350 crank (not advisable with the longer stroke 383 crank). As long as you keep revs under 6,000 or so, the smaller mains won't be a liability. No nitrous, either, but it doesn't sound like that's what you're after.
A dished piston to get compression under 9.5:1 and a Comp XE265H makes for good low-end power and snappy response. All "done" by about 5,600. He LOVES his engine. It does EXACTLY what he wanted it to.