You can't get a pure sinewave UPS in that price. I doubt you can get even a UPS in that price. It's most probably a simple inverter rather than a UPS. A pure sine wave UPS will be about 30-50% more expensive than a regular UPS of the same rating.
I have a couple of Aurora Pure Sine Wave UPSs at my home. The first one is a 1KVA model which is more than 5 years old and it was about Rs. 12,000 when I bought it. The other one is a 1.4 KVA model and I bought it about 1.5 years back for Rs. 20,000.
There is an Aurora shop inside Hyperstar they have a range of UPSs in different price ranges and the pure sine wave models are the most expensive.