Have you looked into Conform'ables? They're fairly expensive, about $100, but you can get them in varying thicknesses, too. I'm getting a shimmed one to bring me "even" in my running shoes.
I imagine your Sidis weren't cheap though, so getting them to work beats starting all over. I've avoided them because they are legendarily "tight" shoes. I can't think of anything known to run more narrow. Specialized's BG shoes I believe are shaped to be a little more in tune with the length of the foot they're fitting, but if you're a skinny 8.5 chances are you'd have the same issue. My fat feet are only happy in Northwaves and my matching tatas get smooshed into Moving Comfort "Phoebe" bras.
"True, but if you throw your panties into the middle of the peloton, someone's likely to get hurt."