With both the Caravan and King Air you might want to ty Solenta, out of S Africa but with operations in many parts of the continent. They fly the Caravan on a number of contracts, including the Red Cross and DHL. Trackmark is another C208 operation that you might want to try.
Heather Stuart owns the place, below are their details:
Trackmark
PO Box 44007
Nairobi-Wilson Airport
Nairobi Kenya
telephone (2) 50 11 04
Solenta Aviation
P O Box 469,
Lanseria, 1748
Johannesburg,
South Africa
Telephone +27 (0) 11 707 4000
One note, there are always a number of pilots who show up in Africa on their own accord, so you will likely find that simply applying will not get you anywhere. If you can't just go without a job in hand (and I understand where you are coming from here but it's not the optimum way to do this), best that you do as much phoning around as possible; you might get lucky.
If you had a friend there you might be able to get a job without showing up, or at least hassling everybody. I recon at this juncture there are still a number of people who either show up or are connected, but with your ratings, and I assume one of your languages is French, you'll be fine. Just bug them.
Good luck, let me know how it goes. Here are a couple more African C208/King Air operations:
Sefofane Air Charters (these guys do tourist camps so more tame than above companies)
P.O. Box 6850
Windhoek
Republic of Namibia
Sefofane Air Charters
P.O. Box 6850
Windhoek
Republic of Namibia
Telephone (+264 61) 25 5735
Telephone (+264 61) 25 5735
Awesome Aviation
Corporate Head Office:
4 Elevation Gardens
Waterfall Park
Midrand
PO Box 7404
Halfway House, 1685
SOUTH AFRICA
International Operations Centre:
Execujet Complex
Lanseria Airport
PO Box 741
Lanseria, 1748
SOUTH AFRICA
Telephone +27 11 541 7260 Midrand
+27 11 540-7500 Lanseria
Naturelink Aviation
Hangar 12 & 45,
Wonderboom Airport
Pretoria, South Africa.
Postal Address:
Naturelink Aviation
PO Box 15585,
Sinoville, 0129
South Africa
Telephone +27 (0) 12 543 3448
Federal Air
Hangar 14
Johannesburg Intnl Airport
Johannesburg, South Africa
Telephone +27 (0)31-563-8020 DRB
+27 (0)11-395-9000 JBG