Oh - one more thing - if you don't have a local supplier, you will also likely not have access to the drill bits you need to bore the hols for these lights. You'll want to order those, too. Plan on spending about $400 for the 2 bits you'll need. Annnndddd, they have a threaded top and they don't come with a shaft to stick into a drill bit. There may be something you can buy and screw in to use as a shaft, but I couldn't find anything, so I ended up having a few 1/2" bolts machined to serve as the shaft that our drills would accept. Kind of a pain in the neck.
A core bit is used to make the first hole, then the grinding spindle is used to dig out the material where the light will sit. When you're done, you'll have a paver that looks like this cross-section: