According to the recent update on Tamashii Web, the Kingdom Hearts King Mickey S.H.Figuarts figure will release January 26, 2018 for 4,536 yen (approx. $40.26 USD).
You can view pictures of the figure below:
This figure was first shown during the the Tokyo Toy Show 2017 along with other Kingdom Hearts figures from the same series. Since then, the Sora S.H.Figuarts has released; the Donald Duck S.H.Figuarts has been announced to release in March, 2018; and the Goofy S.H.Figuarts is set to release in April 2018.
You can pre-order the King Mickey S.H.Figuarts after release from a number of international retailers. Some are listed below for your convenience: