Haven't been there in a long time but you might call Davis Street Fish Market in Evanston.
We eat a lot of raw clams but I purchase at H-Mart and open myself.
My experience with Midwestern Raw Bars is that the product varies and too many times in the past I have had both clams and oysters that were not edible. So I stopped eating them in a restaurant and stopped purchasing oysters completely from any Midwestern source.
But doing this yourself requires a knowledge of Harvest Tags, how to tell if fresh and of course how to open with suitable protection i.e. mesh glove.-Dick