Yup, I think the modification work order for the SAW stocks went out in the late 80's early 90s? There are three stocks they could have used, and they went still went with the wrong one. Regardless, that's not even an M249, it's a Minimi so you'd need to replace it with a Live Resin gun to have it with US forces. I think it would work for UAE in Afghanistan, and French and British forces as well though.
The funny part is the box art illustration shows the correct stock.