It's probably a little thin to help Arthur with his itis, but the lower of these two is my current go-to (the upper was made as a gift).
Like Carl's appears to be, these were made with hardware from
@PersonMakeObject . The only potential drawback, depending on your tastes, is that they're only designed to take the larger blades designed for the big X-acto #2 handles (and/or Swann-Morton blades, but those are a little fancy for me), which aren't quite as common (or as cheap) as the smaller blades.