Sales Org is Master Data which is not supported as a "business field" to restrict code lists. A work around is the following
1. Create a KUT custom field with data type list, which contains all of the Sales Orgs.
2. Create a KUT workflow field update rule on Save of the object to set the custom field = to the Sales Org
3. Create the KUT code list restriction to use the custom field to restrict the codes you want to restrict