There used to be a crop-dusting company in Abidjan years ago, I don't know if they're still there. Mainly banana plantations.
They are still there, I saw them last Jan, parked next to us doing periodic mx. Aircraft looked in good conditions and cared about. I don't have contacts for them (French expats or investors, I guess) but the local flying club is literally on the other side of the hangar's wall. Give them a call.
Alternatively there is a local mx company that works on King Airs and Merlins but I don't remember the name...