This is one of those not so easy to tell things. From the photos only, everything is sort of a guess. You should try a magnet to them and if it reacts, that one is a fake. Although this is far from the only test. Some fakes are made with the exact materials as the originals since they are to be sold as collector items. Some fakes look real and some real coins look fake.
As you said though your intent is to sell them all. You should do everything possible to find out if real or fake prior to atempting to sell. If you can not tell yourself, try to find a coin store near you and just ask. Do not say your selling them, you just want to know about them. The reason is if you mention selling them, you might get all sorts of odd stories.



















