Increase distance between accidentals in key sigs, for the visually impaired

Hello everybody. I have been developing tactile stave scores for the visually impaired (CNC milling) and this feature is badly needed. It would be great if I could adjust space between key signature elements (sharps and flats). For example, now if the key is, say, D major, both F and C sharps are very close to each other and of course it is difficult for visually impaired people to distinguish them by touch. So if I could make space between them a bit bigger it would be really drastically helpful. It would be much easier to recognise them by touch.