It is highly probable that all the manufacturers go on with their business with non-democratic countries since this is a profitable business, and they are free to accept or reject a deal according to their principles. One way or another, these countries always figure out how to get the weapons they need, whether through gun manufacturers or intermediaries.
Gun manufacturers should refuse to sell weapons to non-democratic countries. By doing this, it would limit the weapon flow into countries that are dictatorships, which would in turn limit gun violence. Limiting gun violence in non-democratic countries would keep citizens safer. It may also encourage countries to become democratic so that they could once again purchase weapons.
Yes, arm manufacturers should not sell guns to non democratic countries. In fact, arms manufacturers should stop selling and manufacturing guns entirely, because there are enough guns in the world and they are one of the most evil things to have ever been created. But especially in countries without adequate representation of the people.
Gun manufacturers should not enable non-capitalist countries by selling them munitions. This can only be a bad plan when those weapons are turned against democratic countries. Even worse, governments might get a hold of the guns and use them against their own people. The outcome could be tragic. These companies need to think of the most good for the most people.
No, gun manufacturers should not necessarily refuse to sell weapons to all non-democratic countries. Not all non-democratic countries should be eliminated from gun sales and it is not the responsibility of a gun manufacturer to determine which countries should be denied. Governmental bodies should make that designation and provide a guideline for the manufacturers.