Pushpak was able to get a SL for less than that for the same mileage and time.
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Your lease works out to 33.08 cents per mile. Keep grinding them down til you reach 20-25 cents per mile (with the SV option package you will probably end up closer to 25 than 20). Taking off the down payment (meaning 36 payments of $276) alone takes you down to 27.6 cents per mile. That's a good place to start.
Edit, just noticed you said you already leased it. Perhaps there is still time to change? You can get a better deal than that unless your credit history is bad.