I would bring it to a tire shop that you trust. Sidewall punctures are not repairable. I know this isn't really a puncture, and I know most shops will want to sell you another tire, but you really should get an expert opinion. If the tire structure is not damaged, and it's just a deep scuff, you may be able to keep running the tire.
I just went to Discount Tire since they are just a few blocks from my work. They said it was fine, so I won't worry about it, but I will keep an eye on it. Nice to know they didn't try to sell me something I didn't need.