Harris sells Sugino french cups which work fine on two of my french disasters. Why do you need a new spindle by spinning the fixed cup backwards (really forwards, but it is french)? You will find that the bearing races may not line up. I ran a Campy Victory spindle into the sugino cups for a while. It 'worked', but it works much better now that I have an actual Sugino spindle. You can probably get a wide variety of sizes.