Searching for the definition of a prod, I found this interesting page:
The Crossbows of South-West China
I was not able to find a source for bamboo poles and supplies in South Africa, through a google search though there are furniture manufacturers/importer and builders of bamboo style buildings which you could inquire at.
You also could try contacting the African Bamboo Association listed on this page of Bamboo Organizations
to see if they can help you locate a source.
Africa has only a handful of species indigenous to the continent, and I'm unsure if these species would be suitable or the best suited for your purpose.
However new species have been introduced and a potential source may be to check with botanical gardens in your area. You could check if they have any bamboos growing there, and maybe they could provide you with some material to experiment with.