Regarding Paying With Gold For A Price In Silver
حَدَّثَنَا حُسَيْنُ بْنُ الأَسْوَدِ، حَدَّثَنَا عُبَيْدُ اللَّهِ، أَخْبَرَنَا إِسْرَائِيلُ، عَنْ سِمَاكٍ، بِإِسْنَادِهِ وَمَعْنَاهُ وَالأَوَّلُ أَتَمُّ لَمْ يَذْكُرْ " بِسِعْرِ يَوْمِهَا " .
The tradition mentioned above has also been transmitted by Simak (b. Harb) with a different chain of narrators and to the same effect. The first version is more perfect. It does not mention the words "at the current rate".