Sunan an-Nasa'i, Book 44, Hadith 145 (In-Book) ⓘ
It was narrated that Simak bin Harb said: "I heard Abu Safwan say: 'I bought a pair of trousers from the Messenger of Allah before the Hijrah, and he weighed it for me and allowed me."'
أَخْبَرَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَمُحَمَّدُ بْنُ بَشَّارٍ، عَنْ مُحَمَّدٍ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ سِمَاكِ بْنِ حَرْبٍ، قَالَ سَمِعْتُ أَبَا صَفْوَانَ، قَالَ بِعْتُ مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم سَرَاوِيلَ قَبْلَ الْهِجْرَةِ فَأَرْجَحَ لِي .
also referenced under: Hadith 4593 (Reference) & Volume 5, Book 44, Hadith 4597 (DarusSalam)