Yes. R640 LCD Bezel have a lock and key
The datasheet for the PowerEdge r640 states that you can get and LCD or Security Bezel. However, when manually configuring the r640, the options you can choose are: no bezel, standard bezel, or LCD Bezel.  Looking into it further it seems that the LCD Bezel's lock. I would just like confirmation that the LCD Bezel for the r640 is lockable.
poweredge r640 LCD/security Bezel