Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
حَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، سَمِعَ مُحَمَّدَ بْنَ فُضَيْلٍ، عَنْ إِسْمَاعِيلَ، عَنْ قَيْسٍ، كَانَ عَطَاءُ الْبَدْرِيِّينَ خَمْسَةَ آلاَفٍ خَمْسَةَ آلاَفٍ. وَقَالَ عُمَرُ لأُفَضِّلَنَّهُمْ عَلَى مَنْ بَعْدَهُمْ.Narrated Qais:The Badr warriors were given five thousand (Dirhams) each, yearly. `Umar said, "I will surely give them more than what I will give to others
From Sahih al-Bukhari, whose reports the scholars accept as authentic.