I found a small sink for the head area. It's a 12 inch round copper vessel style that mounts on the top of the cabinet. ( The photos below are from the dealer brochure ) This style solves the problem of drain line interference with the air conditioner compressor that is mounted directly below. The sink drain line can now be routed alongside the compressor and aft to T into the galley sink drain. One 1.5 inch thru hull and seacock will serve both the galley and the head sink drains.
The faucet hot and cold water mixing valve will connect to a matching side spray fixture that will serve as a hand held shower.
The water maker has an output line to sample the end product. This circuit cannot be valved so I will look for a fountain spigot to mount over the sink. The brine reject water line will T into the sink drain below the counter.
