The replacement for the D871 is the D271. None of the parts are backwards compatible.
D271 description:Thumbturn x Occupancy Indicator
Deadbolt thrown or retracted by turn unit only. ...
The Falcon D400 and D800 series (including the D871) were discontinued in 2008.
The indicator on a cylindrical hotel lock is a small pin that projects outward from the face of the cylinder plug (Figure 1) when the inside push button is depressed. When this pin is ...
The Falcon MA mortise lock is available with an occupancy indicator on the following functions: MA301, MA311, MA321, MA371, MA431, MA441(inside of door only), MA451, MA541, MA57...
Related solution: Is the MA indicator available separately?