2" x 2" slots means they are about 50 mm x 50 mm so a 19 mm
diameter coin could easily fit. In fact a 49 mm
diameter coin should fit.
I assume therefore that you are only worried about height.
A US quarter is a mere 1.75 mm thick. Coin capsules like they show in that photo are much thicker. A Coinsafe large round capsule is 44.4 mm
diameter and 6 mm high. That is 3 and a half US quarters thick and there is
still room to spare.
I can't think of any Greek AE under 50 mm
diameter that would be too high for such a cabinet.
I am sure you would be safe. But I am also sure that anyobne you are ordering it from would be happy to give you the full specifications if you emailed them.
Shawn