Damn thats a very high cost, I might be able to get it done in rupees 500 since I just had the cherokee's filter / atf flush done. All for like 500 labour and 400 for the petrol used to clean the ATF filter. But, I knew what I was doing there so wasn't a problem.
And about that filter thing, it has to been changed, after like 150K+ kilometers, the metal bits from the transmission have to tear off with usage and they end up either in the oil pan (where there is a magnet to catch and hold them) or the ATF filter. When the ATF filter gets clogged, it won't let the pressure regulate and there would be no power going to your tyres.