Nitebob wroteTold them they made a mistake advertising a R5000 product for R695, and now don't want to face the music (pardon the pun)
I think you may have shot yourself in the foot right here. If it was a bona fide mistake and you know it (and they know that you know it), I don't think you have much legal standing to force them to give you an expensive item at a fraction of the price.
I'm still very interested to see how this plays out but I think you may have just given away your hand.