One new ITM brand crankshaft front oil seal, part number 15-50001, 13042-A3500, 13042-3510, 13042-73000, 48x70x9.  This fits:

Datsun/Nissan 720 1952cc 06/1979 - 07/1980
Datsun/Nissan 720 2187cc 07/1980 - 1983
Datsun/Nissan 521 Pickup 1595cc 10/1969 - 06/1972
Datsun/Nissan 610 1770cc 12/1972 - 07/1973
Datsun/Nissan 610 1952cc 08/1973 - 1977
Datsun 240Z 10/1969 - 07/1973
Datsun 260Z 1974
Datsun 280Z 1979 - 1983
Datsun 280ZX Turbo 1981 - 1983
Datsun 200SX 1952cc 1980 - 1983
Datsun 510 1595cc 1968 - 1973
Datsun 510 1952cc 1978 - 1981