Link of website:全国信息安全标准化技术委员会 (tc260.org.cn)

Link of document:
标准名称 (tc260.org.cn)

This is the latest draft version from China government regarding data cross border transfer topic:

Document Title: < Information security technology – Guideline for identification of critical data >

http://www.djbh.net/

If you need to know how to perform MLPS assessment in China, Please follow this government website.

http://www.djbh.net/webdev/web/LevelTestOrgAction.do?p=nlbdLv3&id=402885cb35d11a540135d168e41e000c

Via 2nd link you can find all qualified security agencies in China could perform MLPS assessment.

中华人民共和国个人信息保护法-中共中央网络安全和信息化委员会办公室 (cac.gov.cn)

中华人民共和国数据安全法-中共中央网络安全和信息化委员会办公室 (cac.gov.cn)