1758 M 2 Reale - Counterfeit?

This one is hard to be certain of from a picture alone.

The weight is at the limit of tolerance but does not by itself make me suspect a forgery - especially given the apparent corrosion.

The faces of the coin are very rough due to this apparent corrosion. If this is corrosion then look for signs of some similar action on all surfaces including the edge. The edge should normally show corrosive effects at least as significant as one of the faces.

Corrosion like cleaning and deep toning can be artificially applied to cover forgery so be cautious. Any coin without intact surfaces is automatically suspect.

But I do see raised lumps in the fields - those are quite troubling. The doubling you point out is also suspect but possible on a 2R coin. It appears in most cases to be simple Strike Doubling - however the last digit of the date may be double punched.

So is it a forgery? - possibly. I would not bid on it as real and would deduct substantially from a grade as a result of the poor surfaces.