Thanks Jim for your comprehensive response!
I am quite sure that the hilt is cutted from iron and no cast. It looks a bit like that due to the small corrosion pits.
I searched the web for similar examples. The most fitting one might be that one:
The hilt is also cutted iron and it has at least one pas dŽane ring and shows a thumb ring, which I would attribute more to cut-swords. The blade is also quite narrow. The guad is also fixed to the pommel with a screw (same as the one in discussion).
Here are some other but less similar examples, which also show more or less narrow blades:
In my opinion this type of swords have been some kind of a compromise between cut and thrust weapons.
I am not sure about my one, but if I compare it to the shown examples, I think there might be a realistic chance that it is a genuine , rather than a historistic piece.
More opinions highly appreciated.