Shipping is the killer. Woodworkexpress charges 12.99 rockler is 3.99. I had looked at that before sending my link.
Doesn't tell you the mounting plate that is included. Answers on rocklers page indicates that they work for 3/4" overlay.
"Other than that, I've learned enough at this point to have satisfied my curiosity." Well said, that statement sums up many of my partially begun projects, before some other thing catches my attention.