Simple Metal Y Arm file?

[the.ronin]

Sorry I wasn't sure where to post this request. I was hoping someone had a Sketchup file or even an STL of the Simple Metal Y arm? Specifically, just that black plate of the arm.

The reason I ask is I want to use that as a template for making a 2" extension. There are a few extensions out there but I just want something that can look as clean as possible.