SARS rates can be found here.
https://www.sars.gov.za/Legal/Legal-Publications/Pages/Average-Exchange-Rates.aspxA couple of notes on translation of foreign income
1. A taxpayer can elect to utilize either the Spot rate or the average rate
2. One is not obliged to use the SARS rates (as published above), but can use other rates. Note though the onus of proof alway's lies with the taxpayer, so you'd need to be able to substantiate the rate being used. When not using the spot rate, I have alway's used the SARS rates (for simplicity and ease of justifying). Note that if you use daily rates, please keep the proof and source so you can justify it with SARS etc.
3. You need to be consistent in use of rates in each year of assessment. (But can utilize a different method in a subsequent year).