The ARB decal may just be an indication of sponsorship or perhaps to indicate the use of other ARB products like the air lockers?
It doesn't look like it would be difficult to fabricate something like it. Mounting is probably the same as the Westin Safari bar. It may need to be changed a bit so that the bar doesn't obstruct the turn signal indicators. I wish I had the resources to have one made. I like the prerunner look a lot. In terms of functionality, because of the airbags, it's probably not a good idea to have any bars attached to the frame... but functionality be damned. It just looks good. The bar would be a good place to mount a CB whip too... tie the tip to the roof rack etc.