Looking at the installation manual shows one part number equals enough vinyl pieces to do both sides. The first part number you listed comes back with more valid hits on the google machine. I'd go with that one.
I've ordered my fair share of GM parts. Sometimes the part number you order doesn't exactly match up with what shows up on the box, but in the end you get what you ordered (as in it works).
I'd chalk it up to a difference between GM vs. vendor internal part numbers or maybe a different part revision.
BONUS: (INCLUDES PRETTY MUCH THE ENTIRE HOLDEN ACCESSORIES CATALOG INSTALLATION INSTRUCTIONS)
If you check with the dealer I think you find that one is for the 2014/15 year cars and the other is for the 2016/17 year cars ask me how I know . I got a the 2014 stripe on my 2016 . I did not use the front part of the stripe that goes on the front bumper its not the same. You get right & left hand side in one kit.