You could have it honed but it may cost more than a new one. A gunsmith may have hones but not sure if they would have 30mm ones. They would normally only have ones to fit shotguns barrels.
You have the danger of making it worse though if you do not know what your doing. You could inadvertently make the correct bore diameter part wider if you do it wrong.
It took me a while to learn how to hone engine bores so they were the same size from top to bottom with a dedicated honing machine