I see a WX handpiece (with some missing bits), WX-style connectors and no LEDs above the connectors. This is a WXR 3.
But you are right that the front panel says WR 3M. My guess is that the original WXR 3 front panel was damaged and replaced by a WR 3M one (just the black plastic part). They are identical apart from the print.
If you are still in doubt, ask for a photo of the display while powered on. The WXR 3 has a graphical display, while the WR 3M has a 7-segment display.