I have a large selection of used but still operating QSI Electronics.  Some are complete DCDR with Supply Board and Sound board.  Sound only board, and DCDRs.  These were operating correctly prior to removal during an upgrade.  Most include the mounting screw.  Sound boards include battery connector and most have the original speaker.  Prices as shown in drop down menu.  Contact us for specific sound kits, etc.   Rechargeable 9VDC Battery available here.  The 4 pin tether is available elsewhere on this site.