I think this is the thread wildflower was talking about:
https://goccf.com/t/216540
There I don't think the 6 was necessarily altered, but the leaf above it. In your case I don't see any of those markings so I think it is a genuine far 6.
To give you a bit of a reference for price, I bought this one for just under $100 CAD less than a year ago. Not sure if it was a good deal or not but I think it would be the same grade as yours, just without meter marks.



https://goccf.com/t/216540
There I don't think the 6 was necessarily altered, but the leaf above it. In your case I don't see any of those markings so I think it is a genuine far 6.
To give you a bit of a reference for price, I bought this one for just under $100 CAD less than a year ago. Not sure if it was a good deal or not but I think it would be the same grade as yours, just without meter marks.

























