@Nimisha Srinivasa Firstly, Apologies for the delay response!
The pricing is per encryption scope per month. No limit on encryption scope itself. The only limit of auto-rotation of CMK when the encryption scope is configured for CMK and with auto-rotation, that is already documented on the docs as 10K. That does not limit the encryption scope, You can create more and can configure CMK, too, but that CMK can't be configured to auto-rotation beyond the 10K of them configured for CMK with auto-rotation.
If you still have any issue/questions. I would recommend to reach out to Azure Subscription/Billing team, they can provided the details information of the pricing based on the region it's free, and it's the best choice for your scenario.
Please let us know if you have any further queries. I’m happy to assist you further.
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