The other week I was out near 7th and Tilghman, and spotted a seafood place on the east side of 7th.
I didn't have the time to investigate further, as I had to get back to the Easton area. From what I saw, at the very least they offered take-out from a store-front window... couldn't tell if they also did eat-in.
The listings sites mention a seafood market in that area, Atlantic Seafood at 621 N 7th. Could they have expanded to offer hot food?