You would need a 'Coherent' optic fibre to maintain the shape of the display; that is the bundle of fibres forming the large single one are carefully kept in the same order throughout its length. This makes for expense in making and therefore in buying. There would also be the problem of bending it through 90 degrees at the top of the post. The individual small fibres put together by the signal constructor seems to show more promise, therefore.
To use surface-mount LEDs it would probably be necessary to make up a small PC board to which they could be fixed, but that's not a great problem.
The irksome thing is that there are small dot-matrix displays of the right height but capable of showing a number of digits/letters, but it does not appear to be possible to break these down into single 5 by 7 matrices, alas!