FOAK : Cistern make identification please

A pic of the bottom of the push button would be better, these sort are much of a muchness, so any two button one should work. I've got a couple here, nit sure if you can buy them separately. Looks like what come supplied with an Armitage shanks/Ideal toilet.

It is highly unlikely that it will be a non-standard thread, so it would be more useful if you could give an accurate outside diameter for the thread and the number of threads per inch.

Colin Bignell

The people who made the cistern will just have bought in an off the shelf flush valve & button. Any plumbers merchant should have one - although you might have to buy the fill valve as well.

Try Temperate Heating, top of Chatham Hill.