I'm guessing you're in Nepal? That's a pretty good price. That comes to $15 USD. Whereas, it costs $30 USD here in the US. I don't know if there's any tariff or extra shipping cost for you, though.
Have you not tried Amazon? Spigen has an official store with them.
Edit: nevermind, I saw that the domain was "in." for India, but I thought that that symbol was for the Nepalese rupee. I see now that it's for the Indian rupee. So it still comes out a little cheaper, at $24 USD.