"Do not order from abroad" , Customs will not only confesticate it but also send your details to the ISI and they will inturn send you a show cause notice asking you why you should not be prosecuted.
You may think that I am talking out of my arse but unfortunately I am not. I know my stuff very well.
If this is just point to point communication you need this far then there are other solutions that may come handy. Another argument against such a wireless set is that it is unsecure and any one can tap into your conversations. How ever unconfidential your conversations may be but I am sure you dont want others eves dropping right?
For a point to point solution you would need to spend some 4-5k provided there is clear line of sight. You can set up a 2.4Ghz network or a 5.8 if the distance is too much and then have a local wifi network at both ends. Then pick up any voip solution that also works on LAN (there must be plenty that do not need any transit and would work fine on peering within the network). Yes you would need an android at each end and when I say 4-5K I am assuming that you already have one wifi router and have two mobile phones that need to be used one at each end.
A 5.8Ghz set up would work fairly smoothly at 3-4 Kilometres with "jugaad" equipment but if you need stability and your stuff is mission critical then your expenses will sky rocket. A BST alone would cost Rs1.5Lakh + some other tit bits to go with it.