I have a Triton T80si which was leaking.  Analysing the problem it appeared
that the leak was coming from the Stabiliser Valve Assembly (part 82600550 -
see www.tritonshowers.co.uk ). Disassembling the unit, I find that it is
evident that the internal diaphragm within the assembly has split.

Triton want to sell me a whole valve assembly unit for about GBP26 - all I
need is the diaphragm.

Any suggestions where I might be able to get an appropriate diaphragm?
Local plumbers merchants (South Manchester) can't help.

Paul R