I bought a 2009 LE without keyless entry

. Evidently, the dealers can't add it on since it wasn't installed at the factory. I came across a keyless entry system (PN 00016-32901) from trdsparks.com and was wondering whether or not this is a genuine toyota part.
The manual has "Toyota Southeast Distributors" stamped on it. I'm a little scared of adding this on since I am concerned about the reliability of the unit and whether or not it might damage some electronics in the car. Has anyone had any luck installing this keyless entry system?