Answer:
North Korea, Vietnam, Laos, and Myanmar.
Explanation:
Chine borders Vietnam, Laos and Myanmar to the south; India, Bhutan, Nepal, Pakistan and Afghanistan to the southwest; Tajikistan, Kyrgyzstan and Kazakhstan to the west; Mongolia and Russia to the north and North Korea to the northeast;
So the far eastern border countries are: North Korea, Vietnam, Laos, and Myanmar.