Don't go for Nepali providers. They are unprofessional. Well, I should not say this, but that is what I felt because of many unpractical conditions like Radiohead mentioned.

Someone told my brother there is visitor health insurance for 3 months, full coverage at 10 thousands rupees.  Then my brother later found that the insurance is actually useless because they need you to have medical exam by their doctor beforehand, which will cost about 6000 rupees. They will not cover any complications caused by pre-existing troubles their doctors have in record, like diabetic symptom, high blood pressure, asthma etc. Then, why should one pay them if they are just covering minor problems like flu? Also, the health problems due to sport activity and traffic accident were excluded.

There are some US companies who cover 75 to 80% expense. It may cost you around 200 per month per person. You need to talk to them to make sure that they have their health care providers in your area. If you think, regular medicines would keep them healthy, you may not need this insurance.