The Shuishu script (also called Sui script) is not yet in Unicode. The script has a tentative allocation at U+1B300..U+1B4FF in the  Roadmap to the SMP for the Unicode Standard.

A number of documents towards its inclusion have been submitted to the Unicode Technical Committee and WG2:

2014-08-20 Proposal for encoding Shuishu in the SMP of the UCS — China NB ( WG2 N4638,  L2/14-243)

2015-10-22 Preliminary Proposal for encoding Shuishu in the SMP of the UCS — China N.B. (WG2 N4696 part 1,  L2/15-285)

2015-10-22 Introduction of Shuishu Script — Chen Zhuang, Zhao Liming, Yao Qingjun, Wei Shifang, Yao Binglie, Pan Zhongxi (WG2 N4696 part 2,  L2/15-286)

2016-09-24 Updated Proposal for encoding Shuishu in the SMP — China N.B. (WG2 N4696,  L2/16-263)

Recommendations to UTC #149 November 2016 on Script Proposals ( L2/16-342) (See point 9.)

UTC #149 Minutes ( L2/16-325) (See C.7 for decision and action items)

2017-07-26 Towards the ordering of the Shuishu script in the UCS — Michael Everson (WG2 N4839,  L2/17-239)

Recommendations to UTC #152 July-August 2017 on Script Proposals ( L2/17-255) (See point 21.)

UTC #152 Minutes ( L2/17-222) (See C.19 for decision and action items)