Parker Hale Sights .303b

Hello all,

Newbie here.
I have a Parker Hale, 1974 chambered in .303b. The other day the rear sight fell off and got lost. The sight is a flip up sight, has two very small screws on either side and a slide piece for elevation. On this slide piece are indented lines that I guess indicated distance. The piece itself has a V shape and a Half Moon shape cut out on either side.

The picture attached is sort of what I am looking for. But that one does not have the V shape cut out.

If any one can assist me in locating this part, please contact me.

Thank you in advance.

Welcome to the site.
I know Norman Clark Gunsmiths here in the UK have them as PH spares, but I am sure one of the members in Australia will be able to point you in the right direction down there to save you the postage/customs etc.