Hi, It is an E.A. Labratories wiper that was for a time period installed at the factory. I have one with a brass cover and the output shaft on mine is about two inches longer than yours. Different model?
I am no expert, still new to the model a. I found most of my information on
http://www.modelawipers.com/. He also sells arm and blades. Check out the website and you can probably get more detailed info.
Hope this helps.