Here you will find the special selection of Equipment & Goods that would be found in the later years of the 1st Era. It is already assumed that you understand how to purchase goods.
You will not find any of the items from the main game's Equipment & Goods repeated here. Additionally, you will not be able to purchase items from that list either. You are restricted to the items found here. This is due to the simple fact that the technologies and such are vastly different. In an era of guns and such, the more traditional things found in the main game would not apply or would not apply the same. Therefore it is best to just use from this section.
You should also note that you cannot use the crafting section of the main game in this campaign. Such crafting skills do not even exist in this campaign, as really they would have been an archaic art from a long bygone era. It is like finding a swordsmith in modern times Earth. They exist sure, but they are rare indeed and mostly use their skills to make decorative pieces and not true weapons.