This last enemy I killed had a record player, a very valuable item that can be found on the market for 60,000 Kohen
Oh, interesting... so, you can see items found in game to the market. How does it work exactly? How do you get those items in the first place?
Items are obtained on the battlefield, either in chests or in the backpacks of defeated enemies. Items can be crafted from the inventory, by gathering other items, this can give weapons, weapon parts, vests, helmets and many other things.