You can use any relay, the only extra in this relay is the fuse... you can also place an inline fuse between the grille and the relay.
I even put up a wiring diagram for the standard Toyota blue relay (used for headlights/foglights I think) which can be found here.
As far as I know the relay you are looking for is a standard automotive relay, you can just use a Bosch relay.
You can switch the relay on by putting + on the 85 or 86 pin and - on the other. Current then flows from pin 30 to pin 87, switched off current flows from 30 to 87a.