Authentic or fake? coin Era Alexander the Great

I have an offer to buy this coin for 230 €. I like it very much, but am wondering if this  is  a good deal or not. Could it be a fake?

Thank you for your advice.

Romain

4.2 g silver / 18 mm

At first sight it looks authentic, but this is just an opinion.

I think the face was polished a number of years ago — perhaps quite a long time ago. This kind of “enhancement”, unfortunately, used to be done on ancient coins. Here again, it's just a suggestion to further investigate, based on having seen over the years other coins that had definitely been enhanced.

Let's hope others will chime in who are more familiar than I am with Alexandrian (and post-Alexandrian) coinage.

Thank you for your advice!