ENOfficial
It was narrated from Ibn 'Abbas that: He heard the Prophet (ﷺ) say in 'Arafat: "Whoever cannot find an Izar (waist wrapper), let him wear trousers, and whoever cannot find sandals, let him wear Khuffs (leather socks)."
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، قَالَ حَدَّثَنَا مُحَمَّدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ عَمْرِو بْنِ دِينَارٍ، عَنْ جَابِرِ بْنِ زَيْدٍ، عَنِ ابْنِ عَبَّاسٍ، أَنَّهُ سَمِعَ النَّبِيَّ صلى الله عليه وسلم يَقُولُ بِعَرَفَاتٍ فَقَالَ " مَنْ لَمْ يَجِدْ إِزَارًا فَلْيَلْبَسِ السَّرَاوِيلَ وَمَنْ لَمْ يَجِدْ نَعْلَيْنِ فَلْيَلْبَسْ خُفَّيْنِ " .
sunnah.com