Pop up waste plug for bath tub

[noobiediyer]

The bath tub I have should have had a pop up waste something like this:

However, the actual plug part is missing so the bathtub drain looks like this:

As far as I understand, I think the thing that is missing is plug thing with the stalk (sorry, not sure of the proper name) but something like this:

I thought a quick and simple solution was to get a bath plug on a chain (https://www.screwfix.com/p/chrome-bath-plug-chain-16/57174):

This one is 44mm which I believe is standard size. However, this does not fit the drain plug hole size. I am guessing this is because the drain plug hole size is non-standard due to the pop up mechanism.

Does anyone know what the best way forward is?

1. Can you get a replacement pop up thing with the stalk? (the place where I purchased the bath tub waste from do not sell just this part, I would need to buy the whole waste again)
2. Alternatively, can you buy non-standard size drain plugs like the one from Screwfix? Not sure what size I need but I'd guess around 42mm?

Or is the best way forward to replace the whole pop up waste unit in one go?

 

[terryplumb]

Replace the whole pop up waste/ overflo combo if you cant find a plug that fits.

 

[oldbutnotdead]

Have a Google for Universal Sink Plug- there's a few options, sure one will work as a stopgap.

 

[foxhole]

Ideal Standard Replacement 43mm Bath Pop Up Plug E960436NU Chrome

Replacement adjustable bath pop up plug by Ideal Standard.This plug suits the E5800AA waste supplied with many Ideal Standard Steel and Acrylic bath ranges…

plumbinbits.co.uk