I don't know about South African made boats, but I am in the US and own a European Hobie 16 (2000). There are definitely differences in some of the parts, but not all. The mast step, dolphin striker rod and dolphin striker are different as they use a metric thread (for the dolphin striker rod and mast step). The tiller crossbar is also shorter than on a US 16 (meaning the tiller arms are also differnt as they angle inward).
The rudders, rudder castings (upper and lower), trampline castings, extrusions for mast, boom, crossbars and sidebars all seem to be the same. Rigging should be the same as well.
So...my assumption would be that you might find differences between your boat and other...but it will be based on the part. Also...Hobie made changes to parts over the years so just the difference in year of your boat may have an impact on whether its an exact match for your boat.