Perhaps get yourself a used camel rear bumper. Capacity to 8800 lbs I believe.
What are you talking about...
1) Camel never used that vehicle
2) "Camel rear bumper" was a special vehicles item not fitted to any other vehicle but a Tdi Discovery 1, and all that really meant was the sheet metal was either plate reinforced in sections or the standard bumper was fitted but in thicker plate, this was really only to accommodate the tow assembly.
3) Camel rear capacity of its single rear tow point is 5 ton (5.5 ton), bumper itself was not rated for anything.
4) Discovery 3 has an integrated eyelet for towing in the bumper that is about as good as anything else. Zero point to discuss ratings for bumper when even aftermarket ones just fit over existing socket.
To thread question:
Standard rear bumper on a discovery 3 is fine, you may rip the plastic off on a drop. The tactical rovers item is quite good, very thick plate steel. Its swingout is nice and greasable. Other swingout designs exist, and they drill into and weld or bolt to the existing steel bumper that is just under the plastic. Have seen several cars with TR fitted take hits coming off a shelf or backing into things.
Discovery 3 is redonk strong anyway.
https://www.youtube.com/watch?v=3fufTUpi3FU