Tuerca y arandela, tubo de salida

Greetings, I've recently moved into a home that had a 35955-RB-DST faucet. The spout portion wobbles because it was not fully tightened against the granite. The granite thickness won't allow the usage of the clover washer and therefore will not achieve the proper clamp load. To add to the problem, the center hole where the nut is touching does not have adequate landing (chipped/crumbled corners# to provide proper tension in the threaded shank #I can provide a photo if necessary). Is there an extension kit part number I can order that will allow me to use the clover washer? I also don't have the clover washer, or any washer for that matter. On a side note, how can I order the set screws for the handle levers. These were missing too. Thanks, Mike