Yes! You can use your annual statements as well as any other supporting documentation you have to support your cost basis in the mutual fund, including bank records, monthly statements, trade confirmations, etc.
You will need to file your amended return on paper. Be sure to include in your explanation that the broker statement you received was in error and detail the documentation you are including to support your amendment.
If you used Turbo Tax to prepare your 2016 tax return, here is a great link to walk you through the steps:
Amending by 2016 Tax Return in Turbo Tax
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