The watch is exactly the same watch as my 1153S, the later execution dial and hands, I actually prefer this to the early 1153S execution, it's just that bit more 70s, for me anyway. My serial is in the 220xxx series but as I said it is so faint you need the right light and a very good loupe to actually see the numbers, even then they are not much more than spidery elvish runes, sometimes I think I might be imagining them!. I have an earlier one owner first execution 1153N which has been on the same GF bracelet all it's life and the bracelet has rubbed at some of the numbers over the years but they are much, much clearer than on my 1153S, however the 1153N has also never been polished. It may be that the numbers are actually still there on this 1153 but just so faint they are impossible to see with the naked eye.
While it is a shame if the serial numbers are not legible this still looks like a true Carrera 1153S and personally I would prefer a genuine watch with unreadable serial to a fake, no one looks at the serial when you are wearing a watch. Should I ever get my 1153S case refurbished I doubt the remnants of that serial would survive either.
Tony