Bought some in the produce section of Market Basket in Somerville, right next to the hot peppers. I'm gonna assume that I can freeze the extras. FYI, parking is a bitch at this location.
Stop and Shop has them in the frozen section where the other Goya frozen products are. They thaw out nicely and have a good shelf life. As a matter of fact, I have some thawing as we speak for a fish dish I am preparing tonight - I purchased these almost a year ago - product still good.
I have never seen them at Russo's. As you suggest, I always get mine at Asian markets. The OP should expect to pay a dollar or so for a large, thin package that may defrost before you get it home.