HI Duncan,
Firstly, apologies for not answering last year.
I live in West Australia and also drive an auto RHD Aveo (Barina).
I am not aware of anything readily available to bolt on, however, we have a local company, TL Engineering, that does this type of modification for people that need these mods. Wheelchair Lifts & Hoists Perth, WA | Wheelchair Bus Conversions WA See: "Browse Products"
Would there be a similar business near you in South Africa?
I am not suggesting have it made here, as it would need to be custom made to suit your leg length.
cheers George