The Khambu Rai script is not yet in Unicode. The script has a tentative allocation at U+119C0..U+119FF in the Roadmap to the SMP for the Unicode Standard.
A number of proposals for its inclusion have been submitted to the Unicode Technical Committee and WG2:
2011-04-13 Introducing the Khambu Rai Script — Anshuman Pandey ( WG2 N4018, L2/11-105)
2012-10-08 Proposal to Encode Nepal Himalayish Scripts in ISO/IEC 10646 — Pat Hall ( WG2 N4347, L2/12-365)
Review of Indic‐related documents and Recommendations to the UTC ( L2/12-378) (See point II.)
UTC #133 Minutes ( L2/12-343) (See D.10.1 for decision and action items)