There's plenty of military spec 150gr .30-06 out there. I'd not go with the adjustable gas plug unless finding it becomes an issue.
You may or may not get a WWII era service grade. Most of the ones I've seen reported lately have serial numbers well after WWII. My CMP Special has a December 1942 receiver and some WWII hardware (trigger guard, front sight), but then again, the Specials are completely rebuilt and I'd not be surprised if they tried to match hardware to the receiver as much as possible. The service grades don't get quite as much rebuilding as the Specials, so you're likely to get whatever they happen to have.