In versions before 2020 R1, the Country of Origin is greyed out in the New and Amend Stock Item screens. But it is now required when exporting goods, so this add-on allows it to be entered.
The add-on can be freely downloaded from Country_of_Origin.sdbx (right-click and"Save link as")
Install it using System Administrator / Add-ons / Add new add-on. It will work on any version of Sage 200.