Hello Charlie, my name is George,
Those parts are usually specific to the particular shower they come with and usually do not come as spare parts...
You could have a new one made from resin if you can glue the old one together to make a mould. This could be done very easily and the places I use for these sorts of projects are the local college pottery classes & the local garage.
Get the mould made at the pottery class and then take the mould to the local mechanics to see if he will mix you some resin to fill the mould casting.
Do you have the make and model of the shower by any chance?
You are very welcome.
Another alternative would be to have the replacement made by an engineering firm (for preciseness) .. I use one near me, but it would need to be made of either aluminium or stainless steel, and I would imagine that could be quite costly.
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