Get them graded for authenticity. That Patria y Libertad souvenir if genuine could be over $500. Simple Google search says so. Google isn't always right though. Heck, they could be fakes for all I know.
Yes, I am serious. I always used that format, and it never hurt me. Greedy people want to guarantee the highest possible return. If your coins are truly worthwhile, buyers will bid them up. If they aren't worth it, then you'll get what you deserve. ~ Chris
If you feel that way, then keep them until someone knocks on your door and offers you exactly what you want. ~ Chris