One new EPC brand 5/8" bore clutch master cylinder repair kit (made in England), part number SSB901, SSB748, SSB936, 18G8831, BHM7024, 071-1598, 071-1671, 071-7503, SSB1238, SSB1240.  This fits:

Triumph 2000 1966 - 1968
Austin Marina 1973 - 1975
Saab Sonett 1969 - 1974
Sunbeam Alpine 1963 - 1968
Hillman Minx 1963 - 1967
Hillman Husky 1963 - 1967