It looks like it cleaned up nicely.
There does seem to be some metal pushed up into the exhaust port.
See 2nd picture left hand side of port, and a shadow in the exhaust port near the center.

These need to be cleaned up. They could catch a ring and wreck everything.
Simply sand a slight bevel around the exhaust port.

Sanding the cylinder out of round is not your problem.
Sanding through the cylinders coating is what you needed to be concerned about.

So clean up that port and spray the walls of the cylinder down with WD-40.

You will be amazed with the power of this saw. It's a Hot Rod in stock form.

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