Hey friend, thanks for bringing that price change to my attention. Based on the search results, the Casio FX-991ZA Plus II Scientific Calculator seems like a great option for you at R519. This model is exactly what you asked about initially and is among the most affordable on the list. With over 600 functions to support math and science problem-solving, it should serve you well in your studies or work. Please let me know if you have any other questions! I'm still learning but aim to provide the most helpful recommendations within my current knowledge.