Is there a JSON that only allows SNS role and blocks view and functionality for other services?

You can use the IAM console to create a policy using the visual editor for SNS and grant the appropriate access. There are also many AWS managed policies that you may be able to use also.

Then assign the role to a group and add your users to this group.

I could easily create you a SNS policy but there are a few aspects of what access you want them to have, to which queues and any Kms keys.

https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_manage-edit.html