So contacting direct flight in Zambia would be my first phone call.
Just so you don't waste a lot of time hunting this mythical Direct Flight in Zambia, it's
Proflight Zambia. A J31 will be severely limited. Used to operate the J31 and J32 out of Lusaka. J32 is better however not much and WAT limits, plus availability of suitable alternates due facilities will hamper payload. As MJ says, water meth will be a necessity on the J31. May as well go ahead and remove a row of seats also. You'll never need the full complement, and it removes the temptation.
Other factors to consider are lack of facilities at most African internationals, so GPUs will not be widely available and there is no air conditioning until the engines are running. Sitting in an aircraft that's showing 48ºC cabin temperature, with all the passengers soaked, will no doubt hamper your client retention abilities.