I bought a stack of these when they were being pulled out of the Eclipse jet fleet. I used some of them but have two spares available.
The 400W is a GPS only unit (the 430 is the version with the radio included). W signifies that it can do WAAS precision approaches and also serve as a source for ADS-B.
I've used these coupled to SL40 and SL30 radios, so I can have a separate user interface for the radios but still be able to take update frequencies from the 400W over the serial data bus. I just installed one in the 150 I'm rebuilding now as an upgrade to the older Garmin GPS, so I can drive the forthcoming Trio autopilot with it. All it took was pulling the pins from the old connector and inserting them in the new one.
$2000 for the GPS, datacards, mounting tray, and backplate.
