I don't read Nepali, but thanks to the excellent Appendix on Unit Markings in John Walter's
Guns of the Gurkhas I believe the Devanagari characters on the trigger guard of your Martini mean:
Gorakhdal Company
No. 8
Gorakhdal Company was one of many independent companies of the Royal Nepalese Army. It was formed in 1880. The number is either a rack number given to the weapon, or the number of an individual rifleman to whom the weapon was assigned.