I'm a little out of touch with what goes on in the GA market in Africa. But I do know that generally an ICAO ATPL is required. There are some outfits operating N registered aircraft here though and so you might stand a chance. If you want some good info, look through the Rossair thread as well as the Maun Old Boys thread here in the Africa forum. Most of those lads are flying in exactly the jobs you're talking about, and would certainly be able to point you in the right direction; even if it is into the jaws of a croc waiting for you at the bottom of the Delta!
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