"The Last Lion - 1972" was released on DVD in March 2012. The screenplay was written by Wilbur Smith.
A hunter pursues a lion, engaging in an epic battle with it. The theme of the film is loosingly taken over in part of WS' book "A Time to Die (1989)" (as far as I remember it, but my memory could play trics on me).
Hope the info helps to answer your question.
An small update - Just to be complete
"The Kingfisher Caper" filmed in 1975 has the same storyline as "The Diamond Hunters" filmed in 2001.
All are availble on DVD except The Kingfisher Caper which can only be sourced as a VHS.