Yes there should be a cover over the cam. Unfortunately it's not cheap.
Here's the details.
Part Number LDL10001L, the L standing for Landrover
Description PLATE-BLANKING
You'll need to check the screw size, as 2 are listed.
Screw M8 x 16 with integral flange.
Part Number FS108165
Description SCREW-FLANGED HEAD
Screw M6 x 25 with integral flange.
Part Number FS106255L
Description SCREW
Plucked from the Internet.
Hope this helps.