Foreign instructor rating conversion/renewal

[v6g]

I hold a Canadian Flight Instructor Rating (Class 4 - that's a newbie instructor rating in the Canadian system). Under the Canadian system it has to be "renewed" every 12 months by way of an instructors flight test - mine is up for renewal in November.

Now, I'm planning on going on a job-hunting trip around southern Africa September - October timeframe.

My question: If I were to find a job that utilises my instructor rating in Bots/Namibia and get my license converted, does anyone know if my flight instructor rating would be unusable in Africa once it's expired in Canada? Would I have to return to Canada just to get it renewed or can the aviation authorities "down there" handle renewing a foreign-expired rating? Basically, should I renew it in Canada before I leave or can it be renewed once down there?

Thanks!