The IFD510 will be announced at NBAA on Monday. The 510 is a 540 without the VHF radio.  It hasn't hit the www.avidyne.com website but should be there very shortly. 

The IFD510 is a slide-in replacement for existing GPS500/W GPS-only navigators found in many turbo-prop and light jet aircraft, and is an extension of Avidyne’s recently-announced plug-and-play avionics line, which includes the IFD540, touch-screen FMS/GPS/NAV/COM.  Avidyne also announced today that all of their panel mounted avionics, including the IFD510, the IFD540, the AMX240 Audio Panel, and the AXP340 Mode Transponder with ADS-B Out, will be available with optional grey bezels which are designed to be more aesthetically suited to match the other avionics in typical turbine-class aircraft panels.