Hello Vic
The master cylinder is Girling.
The originals had a very large reservoir,and are
available from Rory at Marcos Heritage. How ever the Triumph GT6 version is
Girling part No 64068832 and should be available from Rimmer Bros UK. They are
about £30 as apposed to around £120 from Rory, but they do have the smaller
res'.
regards Jack York UK
#4057.