In order to determine what Unicode symbol should be associated with that character, one would have to ascertain what the dot pattern was supposed to represent. The particular pattern of dots used for the character was chosen to fit in a 5x8 matrix, and some design aspects might have been different if a different size of matrix had been used. In a 7x9 matrix, for example, there might have been four illuminated pixels on each side of the shape rather than three, or the shape used for the 5x7 matrix might have had a frame added around it (trying to have a frame around a checkerboard pattern in a 5x5 area would make the middle look like an "X" or "O" rather than a checkerboard). If one assumes the goal was to have a shaded square which does not fill the character box, I think Unicode points 25A7 through 25A9 ("Square with [different kinds of diagonal] Fill") would all be perfectly reasonable candidates, with 25A9 probably being the best. Point 25A9 looks reasonable in both normal and fixed-spacing fonts: ABC▩EFG and ABC▩EFT; it's centered within the X height, but shorter, and its interior is filled but not solid.

In order to determine what Unicode symbol should be associated with that character, one would have to ascertain what the dot pattern was supposed to represent. The particular pattern of dots used for the character was chosen to fit in a 5x8 matrix, and some design aspects might have been different if a different size of matrix had been used. In a 7x9 matrix, for example, there might have been four illuminated pixels on each side of the shape rather than three, or the shape used for the 5x7 matrix might have had a frame added around it (trying to have a frame around a checkerboard pattern in a 5x5 area would make the middle look like an "X" or "O" rather than a checkerboard). If one assumes the goal was to have a shaded square which does not fill the character box, I think Unicode points 25A7 through 25A9 ("Square with [different kinds of diagonal] Fill") would all be perfectly reasonable candidates, with 25A9 probably being the best. Point 25A9 looks reasonable in both normal and fixed-spacing fonts: ABC▩EFG and ABC▩EFT; it's centered within the X height, but shorter, and its interior is filled but not solid.

Another possibility would be 203B "Reference Mark" which looks like "ABC※EFG" or ABC※EFG. It wouldn't match the dot pattern when magnified, but one would hardly argue that character 0x2F shouldn't be recognized as a slash, but rather as a diagonal sequence of five dots. Someone given the task of representing ※ in a 5x7 matrix would be likely to produce the exact same pattern of pixels as Apple used for their 0x7F character.