Sapphire glass camera replacement

Hi everyone! My girlfriend broke her camera lens only two days after having her new iPhone, so I'm looking for the best possible replacement. Unfortunately, I can't seem to find a sapphire glass lens. Where can I find it? I live in Italy but I would be willing to order it from any other country.

I was also wondering what's the best glue I can use. I replaced my iPhone 6s lens many times and I never found the pre-applied double-side tape that effective: it doesn't seem to adhere that well and it makes the camera stick out too much. Is the T-8000 the best option? And do you have any advice on how to apply it in the best way? I want to prevent any water to get inside.

Thank you so much in advance! I hope you're having a nice day.

Erik