There is a new machine at the Saloon. It looks like some kind of dispenser. It also seems to give you random items in return.

There are two different tiers of lootboxes. Basic and premium.

Basic tier costs 10 Prairie King tokens and the premium costs 50.

The premium tier has a higher chance of dropping rarer items (and more of them).

You can find all of the items and the drop chances of them here:

This mod adds a lootbox mechanic to the game. It uses the coins that you receive from the Journey of the Prairie King game as currency.