Ancient toilet cistern

[rktatschner]

I am faced with a very old Twyford toilet cistern. The syphoning assembly is made of china (as opposed to plastic) and the diaphragm is split.

Is there any way of knowing if a modern syphoning assembly will fit the outlet?

Is there any way of getting a replacement diaphragm or what could I use to make one?

 

[PTH]

I made a diaphragm for a porcelain syphon from the lid of a margarine tub! I presume that it's still working. As an alternative, most modern syphons have a larger cross-sectional area than old ones (to produce a effective flush from 6 litres of water) You could remove the old and offer it up against the range available in your local plumbers merchants - the likes of Q&B will probably only have one make in stock.
Good luck.