Hi, Shah, the machine we are talking about is Philips Respironics CoughAssist. I am not sure which medical equipment distributors cover Nepal but I know some are based in India. If you are able to arrange shipping yourself, you might look on sites like dotmed for used units; if necessary, the unit could be shipped to you and you could ship it to Nepal. If you contact Philips directly via its Web site, perhaps they can refer you to a distributor.
If your dad does not have a suction machine, much less expensive, that might be another helpful aid for him and you could procure a new one.
BiPAP settings require adjustment to be most effective so I would also make sure he has someone who can adjust his settings; post further in a new thread if you need help in that regard.
Best,
Laurie