Sorry for the delay in answering. I believe that model is probably discontinued. I actually found one just like mine on Ebay. Here's the link: http://www.ebay.com/itm/152405877188
(or) if you'd like better pictures I could take a few of mine?
If you'll note in magnified photo of the clamp bottom portion, you'll see a collar attached to the bottom of the riser pole. And attached to that collar is the plate & clamp assembly. I could probably drill an additional hole in the back plate thus having 3 holes from which to bolt it to the wall. But you'd still have that collar sticking out. Maybe I should call Ergo to see if they have a part I can use to assist in modifying wall conversion?
Thank you Adam!