One new Geon brand brake master cylinder repair kit, part number KL71535.  This fits:

Hillman Minx Series 1-3C, Series 5 & 6 1956 - 1965

Hillman Super Minx MK2, 3, 4 1962 - 1967

Hillman Husky 1958 - 1962

Jaguar MKI and MKII 2.4L & 3.4L 1956 - 1959