I don't think its hat simple
You need to think in terrms of imporrt substitution, and focus on what you guys actually need to fill supply chain gaps, and within that, what is actually feasible
then you need to see what protectionist or financial assistance measures are legally/fiscally feasible, and place a sunset clause on them so that once the new industry is established, it will be forced to remain competitive
All of this depends on a proper examination of what Orania's biggest local trade links are, what is costing too much, where you have comparative advantage, blah blah blah
Like, basically its an empirical question that you cant answer without reasonable data
But i would suspect you would benefit most from primary processing stuff - building materials, basic agriprocessing and packaging, maybe some elemental metals stuff if it can be one at a reasonable scale
But then you need to do something about the transport situation - those roads are a nightmare, and the transport costs can make a lot of export products uneconomical