Capcom has announced Monster Hunter Stories will be releasing in Japan for 3DS on October 8.
This news comes from Gematsu, who also say it will cost 5,800 yen (~$53) at retail and 5,546 yen (~$51) to download.
There will also be three amiibo figures launching alongside the game, that will unlock special in-game monsters. "One-Eyed Rathalos and Rider (Female)" and "One-Eyed Rathalos and Rider (Male)" each cost 1,800 yen (~$16), and "Nabiru" costs 1,200 yen (~$11). A second set of amiibo will launch after release.
If you already have a Monster Hunter Generations save on your 3DS, you'll get an additional Dinovaldo costume for Nabiru.