Genuine Honda from 3S: Rs.34,000/- excluding paint and fitting
But for alternate options, @Spano is the best source to guide you through its purchase, paint and installation.
Personally, I'd spend the money where it really matters such as a Premium Ceramic Coating with one-year warranty OR TEIN Performance Springs, a beefier intercooler (For Turbos) etc etc. The aftermarket one's finish is very close to the genuine one except for the LED Stop Lamp.