First off, apologies on the first post I made on this. The ORIGINAL SOURCE is Popular Mechanics.
Popular Mechanics also mentions that Nerf will be selling separate accessories. From the source link.
“Nerf fanatics who love customization shall not be disappointed. The butt can be swapped out for other accessories. Nerf will sell laser sights for the foam sniper in you.”
And finally, we have the official product description, USA pricing, and targeted release frame for the USA below.
Nerf N-STRIKE ELITE DEMOLISHER 2-IN-1 Blaster
(Ages 8 years & up/Approx. Retail Price: $39.99/Available: Fall 14)
Take NERF shots to the next level with the 2-IN-1 blaster that dominates both MEGA and ELITE missions! The DEMOLISHER 2-IN-1 blaster is impressive in size and power firing up to 100 feet, featuring semi-motorized blasting, a 10 dart banana clip, and all new missiles. Connect NERF scopes and lights to the blaster’s top Tactical Rail System and set sights on some of coolest NERF shots performed. Blaster includes two missiles and 10 N-STRIKE ELITE darts. Four AA batteries required, not included. Available at most major retailers nationwide and HasbroToyshop.com.