The craftsmen in India are known for the extreme variety of instruments they make. I have never seen a dilruba or esraj this large, so I have not bothered to figure out the correct gauges for the strings.
I will still do what I can to help you. If you measure the length of the string from bridge to bridge, and email me the details at firstname.lastname@example.org, I will try and figure out some workable gauges and email the info back to you. Since this is an unusual size, I would also appreciate it if you could tell me whatever you know about your instrument. Info such as, when it was built, and where it was made, would be extremely useful for me in helping others.
Peace and Solidarity
© 1998 - 2017 David and Chandrakantha Courtney
For comments, corrections, and suggestions, kindly contact David Courtney at email@example.com