Managed to rescue my Mum's Bernina 707 sewing machine that was about to go to the dump.
The capacitor has failed (otherwise it is in great condition). Having looked into it, it appears that replacements are obsolete. however I've found a few references to recreating the same capacitance using new ones from Maplin, etc. People have mentioned just wiring a couple of 0.1 µf in series (400 or 500v?), and connecting to the three non-earth wires. (apparently the motor is double insulated so you don't actually need to connect the earth wire).
Usefully, the capacitor has a wiring diagram on it. I have the soldering iron & kit to do the repair, but if someone could help me identify exactly which capacitors to get (from RS?), and how to connect them, that would be awesome!!
Photos here, including the wiring diagram. Any pointers much appreciated!!
Edit: If I don't need the earth wire, then that takes two of the capacitors out of the equation (see diagram in the link above), so would this then work with a 0.06µF and 0.02µF connected across the white, black and grey wires? What voltage / which components should I get from the myriad on RS?