Guzzi, that is a general rubber insulated clamp (1/2 inch) I was trolling hardware stores for a while looking for the most appropriate thing. I was contemplating fabbing a clamp and then dipping it in plastic but this worked out great and they are relatively cheap. I did not have to do anything for the brake line with the speedo cable but I had to put a piece of rubber hose around the other cable (I took a small sliver from the stock brake line that had it for protection) and used that to fill the void so it was very snug on the solo line.
I picked up two stainless steel metric bolts and used those in the place of the stock ones because I am using them up top to secure the bracket for the fender. I will have that this week and will mount it this Sunday.