A similar alternative would be the Kuryakyn Duallys with the stirrups(heel rest). These look a lot more sturdy. The switchblades are a good idea, but during an 80 MPH bu++ relief session, I'd hate to put my 230 pounds on that little heel piece.
I believe our part numbers for this would be:
Adapter #8840
Duallys #7963
Stirrups #4028
Duallys + stirrups #8062
Check with your dealer or Kuryakyn to make sure.
Dennis