Board Thread:Naruto Gaiden/@comment-26387606-20150510193623/@comment-1018594-20150510195406

KiumaruHamachi wrote: Between chapter 698 and 699, both Naruto and Sasuke both received new arms.

It was stated in 699 that Sasuke left the village before his prosthetic arm could be finished. In Kakashi Hiden: Lightning in the Icy Sky, a few months pass before Naruto receives his as well.