Here is a complete list of known varieties which can be found in mint sets. You can see all of them photographically documented in my E-book, What Are Die Varieties?"

1948 Mint Set
1948-S 1c RPM-001

1949 Mint Set
1949-D 5c OMM-001

1954 Mint Set
1954 5c DDR-001

1959 Mint Set
1959-D 1c RPM-013

1960 Mint Set
1960-D 1c RPM-001
1960-D 1c RPM-023

1961 Mint Set
1961-D 50c RPM-001

1963 Mint Set
1963 10c DDO-001
1963 25c DDO-001
1963 25c DDO-007 & DDR-001 (comes both with and without DDR)
1963 25c DDO-008
1963 50c DDO-002
1963 50c DDR-001
1963 50c DDR-004
1963-D 1c RPM-012
1963-D 1c RPM-016
1963-D 5c DDR-004
1963-D 25c DDO-001
1963-D 25c DDO-002

1968 Mint Set
1968 10c DDO-001
1968-D 25c DDR-002

1969 Mint Set
1969-D 5c RPM-001 = Delisted
1969-D 10c RPM-001
1969-D 25c RPM-001
1969-D 50c DDR-001 (flared G of reverse designer's initials)
1969-D 50c DDR-004

1970 Mint Set
1970-D 1c DDO-001
1970-D 10c DDR-001
1970-D 10c DDR-003
1970-D 10c DDR-004
1970-D 10c DDR-005
1970-D 25c DDR-001
1970-D 25c DDR-002
1970-D 25c DDR-004
1970-D 50c DDR-001 (flared G of reverse designer's initials)
1970-D 50c DDR-002 (flared G of reverse designer's initials)
1970-D 50c DDR-003 (flared G of reverse designer's initials)
1970-D 50c DDR-004 (flared G of reverse designer's initials)
1970-D 50c DDR-006 (flared G of reverse designer's initials)
1970-D 50c DDR-007 (flared G of reverse designer's initials)
1970-D 50c DDR-008 (flared G of reverse designer's initials)
1970-D 50c DDR-009 (flared G of reverse designer's initials)
1970-S 1c RPM-001

1971 Mint Set
1971-D 5c RPM-001
1971-D 5c RPM-004
1971-D 10c RPM-001
1971-D 50c DDO-004 & DDR-002
1971-D 50c DDO-006
1971-D 50c DDO-007

1972 Mint Set
1972-D 5c DDR-001
1972-D 50c DDR-002

1973 Mint Set
1973 50c DDR-001
1973-D 50c DDO-002

1974 Mint Set
1974-D 50c DDO-001
1974-D 50c DDR-001

1976 Mint Set
1976-D 25c DDO-002
1976-D 50c DDO-001

1981 Mint Set
1981-P 25c DDO-001
1981-D 5c DDR-001

1984 Mint Set
1984-D 50c RPM-001

1987 Mint Set
1987-D 10c RPM-001

1989 Mint Set
1989-P 10c DDR-001
1989-P 25c DDO-001
1989-D 5c DDR-001
1989-D 50c RPM-001

1991 Mint Set
1991-D 5c DDR-001
1991-D 5c DDR-002
1991-D 5c DDR-003
1991-D 5c DDR-004

2005 Mint Set
2005-P Bison 5c DDO-001, 2, 3, 4
2005-P OIV 5c DDRs (1-21)
2005-P OIV 5c DDRs (22-42)
2005-P OIV 5c DDRs (43-60)
2005-P MN 25c DDR-004, 33, 38, 47, 49, 54
2005-D MN 25c DDR-001, 3, 4
2005-P OR 25c DDR-001, 2, 3, 5, 6, 7
2005-D OR 25c DDR-001, 2, 4, 5, 6, 7, 8, 9

2007 Mint Set
2007-P WY 25c DDR-008, 16, 17

2008 Mint Set
2008-D NM 25c DDR-001, 2, 3, 4

2009 Mint Set
2009-P DC 25c DDR-014
2009-D FY 1c DDRs (1-8)

Thanks,
James Wiles