The sources I've seen say the original Centurions came from Britain and later India and Jordan.
If SA acquired Sho't Kal from Israel during the early 1980s it is news to me, but not entirely impossible, there was a lot of "under the table" dealing going on at that time that has only become known to the public recently. However many sources report that "scrap" Centurions from India were the basis of the Semel and Olifant upgrade programs.
I have found a source that says the Semel was based on the Sho't Kal - built on "scrap" hulls bought from India -
http://www.globalsecurity.org/military/ ... lifant.htmBTW the basic difference between the Sho't and the Sho't Kal is that the Kal is an upgrade that replaced the original British petrol engine with a Teledyne Continental diesel engine.
This page contains a detailed history but as it is written for game players it may not be entirely reliable -
http://www.pmulcahy.com/tanks/south_african_tanks.htmlThis is DefenceWeb's Fact File - reliable but not very detailed -
http://www.defenceweb.co.za/index.php?o ... Itemid=159Army Guide - use with care, the site is not considered reliable by Wikipedia -
http://www.army-guide.com/eng/product894.html