Assuming the 10M records is ~2000M input tokens + 200M output tokens, this would cost $300 to classify using llama-3.3-70b[1]. If using llama lets you do this in say one day instead of two days for a traditional NLP pipeline, it's worthwhile.
[1]: https://openrouter.ai/meta-llama/llama-3.3-70b-instruct