I do have these on order from Moulded Shoe:
Should they ever come in, I think that will have my pebble grain boot needs taken care of. I also have an MTO from another shoemaker in the works that will combine pebble and shell. We'll see which I get first.
Appreciate the tip on other makers' pebble grain options, though. I don't really know anything about C&J or AS, so it's good to hear they offer some nice makeups along these lines.