Sorry. Haven't been on the forum in a while. It's been a zoo around our shop the last couple of weeks and I don't have Internet at home. Have to sneak on he forum when my wife's not looking... She's the boss.
The cheapest way by far to print them is in black ink, meaning the photos will be grayscale. Color gets really expensive, as you know printing the NACA. Some people print newsletters in red or blue ink, but to me photos look better in grayscale than in a solid color.
Either individual 8.5" x 11" 2-sided copies stapled together or 11" x 17" sheets folded in half will work great. The folded 11" x 17" is also cheaper than the individual sheets and no stapling is required.
Unfortunately, I don't have a "mail merge" program for the addressing, as we don't do any bulk mailing. But usually you can find local printers or bulk mailing places that specialize in that.
Turnaround time should be only 3 or 4 days.