Not that difficult......
Your broker would normally provide a paper or pdf file monthly of your account.
You need to make a copy of the statement (physical or digital) and blank out the account number and any other info not required and paste that into your email with the cruise confirmation number.
Based on your computer skills, you may want to just print out the page, mark out the sensitive data, take a digital photo of the redacted page and attach or paste it into you email.
That is it.