Since you seem to be interested in this style and live in such distant place, I have bothered to make little research for you on porters in South Africa. Here are my findings from best to worst according to ratebeer.com

Devil's Peak Brewing Company - Devil's Peak / Fierce Beer - Imperial Café Racer -Salt River, Cape Town

Copperlake Breweries - Copperlake Robust Porter - Gauteng: Sunrella
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Red Sky Brewing Company - Red Sky Vampire - Western Cape: Gordons Bay

Mad Giant - Mad Giant Cab Franc Barrel Porter - Johannesburg

Hopefully, you will find at least one of them.