Thanks folks. It's a shame Mark Copplestone never did figures for the Savannah kingdoms, but there is enough to work with from his many other ranges. I also have some of the North Star African Heavy cavalry tucked away somewhere, so will have to get those put together at some point.
Mark - Thanks for the link to Castaway Arts. I don't know how easy it is to get them posted to the UK, but might have to give it a go. Some of the cavalry they do look very useful!