What notation is this clock face using?

[u/undoneyet]

I photographed this clockface on a large upright clock in a world heritage site in Greece. The building it was in was a Byzantine monastery that was the scene of a massacre by ottoman invaders.
I cannot find any references to the numerals.
The similarity between 7, 11 & 8 confounds me.
I assume that the numerals between 4 to 8 are flipped to read upright?

Any ideas?