I believe actually that the ONLY rear fender available from Honda is the US spec K1 type (3 bolt lamp bracket mounting) No UK ones are available and the correct sandcast (2 bolt lamp bracket mounting) US spec one is also NLA.
So, if absolute correctness matters, nothing is actually available NOS direct from Honda unless you are restoring a US spec K1. We all have to decide what compromises are acceptable to us given finances, deired end result (rider, show bike, ....).
Chris R.