Dear @Christa, according to Wikipedia:

"in terms of the South African Patent Act 57 of 1978, the Companies and Intellectual Property Commission (CIPC) is the custodian of all new patent applications that are filed within the Republic of South Africa. An individual can privately file a provisional patent application. However, only a patent attorney can file a non-provisional patent application and assist in drafting the patent specification ... is essential that the content of the patent specification - referring to the definition and description of the invention - is clear, coherent and concise so that the patent is assured the maximum protection. Protection is granted for twenty years from the filing date of the non-provisional patent application."

The link below gives you some information, it seems precise. All the Best! :))

https://en.wikipedia.org/wiki/South_African_patent_system

CONTACT:

http://www.wipo.int/directory/en/contact.jsp?country_id=190&type=ADMIN_IPO

The application may be submitted by individual or legal representative.

Note that when applying for patent you have to disclose in details your subject matter (invention); thus, the invention or process is no longer a secret. During the contest period, the information will be published. Double check the requirement for your use of the claim PATENT PENDING during the period prior to patent issuance---and how much enforcement does local law permits with Patent Pending notice. Look into the country's status under WIPO how extensive is the patent of the country in the international market, i.e. IP treaty ratification, etc.

http://www.wipo.int/directory/en/contact.jsp?country_id=190&type=ADMIN_IPO

http://www.wipo.int/directory/en/urls.jsp