If you look this site at member downloads there is a manual for the TS 42 plough, the spares list shows the different mouldboards/ shares that were available for this plough, including the part number.
Finding one is more difficult, there are people who have old stocks of plough parts and break up old ploughs for parts.
I don’t know if a modern mouldboard could be adapted to fit.
Sometimes it is possible to find incomplete ploughs that have the parts you need on them.