These steel dies were engraved by hand at actual stamp size - an artistic feat requiring an exceptional degree of skill.
Cards fund the Australian Philatelic Federation (APF). Revenue from the sales of stamp replica cards will pass to the APF, known previously as the Australian Stamp Promotion Council. The APF has been granted exclusive rights to use the original steel dies to produce the stamp replica cards. {Early cards were sold by the APF for $4 each - later cards are now selling for $6 each from the APF}.
No Postal Validity. The stamp replica cards are philatelic souvenirs only and have no postal validity. Consequently, no first day of issue postmarking or any other type of postmarking will be permitted by Australia Post. {But see images below

(Source: Stamp News, June 1985 - article reproduced below)
As at 24 Feb 2014, there are 49 different cards, with plans for a 50th card to be released by Australia Post in 2015 (believed to be part of Anzac centenary - so likely to be a replica card of the 1965 "Simpson and Donkey" stamps that were also issued by Nauru, Christmas Island, Cocos (Keeling) Islands, and Norfolk Island).
Some cards were produced in limited numbers in black - provided to volunteers at Australian stamp shows, or as part of Supporters Packs.
Recent cards are still available for sale from the Australian Philatelic Federation website at http://www.apf.org.au/products.htm, but are progressively withdrawn.
Reference Numbers (SRC "prefixes" are those provided by Seven Seas Stamps (in the Australasian Stamp Catalogue Volume 1: Australia and Territories, or assumed as a logical extension). The Seven Seas Catalogue provides catalogue values, which are not recorded here. Buy the catalogue!
Number - Issue Date - Description
SRC 1 - Mar 1984 - 1914 Unissued 2d King George V, 1/- Swan (AUSIPEX 84)
SRC 2 - 21 Sep 1984 - 1934 Victoria Centenary (AUSIPEX 84)
SRC 3 - 15 May 1985 - 1963-64 Pre-Decimal Navigators
SRC 4 - 30 Sep 1985 - 1935 Silver Jubilee of King George V
SRC 5 - 21 Apr 1986 - Queen Elizabeth Stamp Portraits (1959-1962)
SRC 6 - 4 Aug 1986 - 1936 South Australian Centenary
SRC 7 - 1 Dec 1986 - 1957 Christmas
SRC 8 - 20 Mar 1987 - 1959 Unissued AAT 4d, 7d
SRC 9 - 1 Jul 1987 - 1961 Centenary of Dame Nellie Melba's Birth
SRC 10 - 15 Oct 1987 - 1958 Christmas
SRC 11 - 1 Feb 1988 - Flights of Sir Charles Kingsford Smith
SRC 11b - 8 Apr 1988 - Flights of Sir Charles Kingsford Smith (Overprinted Aeropex 88)
SRC 12 - 9 May 1988 - 1927 Opening of Parliament
SRC 13 - 3 Oct 1988 - 1959 Christmas
SRC 14 - 6 Feb - 1989 Robes
SRC 15 - 14 Jul 1989 - 1937 NSW Sesquicentenary
SRC 16 - 18 Sep 1989- 1960 Christmas
SRC 17 - 7 Feb 1990 - 1949-50 Arms of Commonwealth of Australia
SRC 18 - 13 Jun 1990 - 1940 Australian Imperial Forces
SRC 19 - 31 Oct 1990 - 1961 Christmas
SRC 20 - 14 Feb 1991 - 1932 1/- Lyrebird
SRC 21 - 6 Jun 1991 - 1935 ANZAC Commemoration
SRC 22 - 1 Nov 1991 - 1962 Christmas
SRC 23 - 19 Feb 1992 - 1932 Sydney Harbour Bridge
SRC 24 - 2 Jul 1992 - 1956 Olympics
SRC 24b - 1992 - 1956 Olympics "Back to Australia" Private Overprint
SRC 25 - 30 Oct 1992 - 1963 Christmas
SRC 26 - 14 Jan 1993 - 1968 Namatjira Booklet Pane
SRC 27 - 7 Apr 1993 - 1953 Coronation
SRC 28 - 1 Jul 1993 - 1929 Swan
SRC 29 - 1 Oct 1993 - 1974 Christmas
SRC 30 - 3 Feb 1994 - Australian Flora
SRC 31 - 12 May 1994 - Zoological Definitives
SRC 32 - 11 Aug 1994 - Prime Ministers
SRC 33 - 18 Nov 1994 - 1934 Air Mail
SRC 34 - 19 Oct 1995 - 1959 Post Office Anniversary
SRC 35 - 17 Oct 1996 - 1948 Von Mueller
SRC 36 - 14 Mar 1998 - 1958 War Memorial Pair
SRC 36a - 14 Mar 1998 - 1958 War Memorial Pair (Black Print)
SRC 36b - 2013 - 1958 War Memorial Pair (Overprinted for 80th Anniversary)
SRC 36c - 14 Mar 2014 - 1958 War Memorial Pair (Overprinted for Canberra Stampshow 2014)
SRC 37 - 19 Mar 1999 - 1914 Kookaburra
SRC 37a - 19 Mar 1999 - 1914 Kookaburra (Black Print)
SRC 38 - 5 Nov 1999 - 1955 Centenary of South Australia
SRC 38b - 2005 - 1955 Centenary of South Australia (Overprinted for South Australian Stamp Anniversary 1855-2005)
SRC 39 - 15 Sep 2000 - 1956 Olympic Torch
SRC 39a - 15 Sep 2000 - 1956 Olympic Torch (Black Print)
SRC 40 - 22 Oct 2001 - 1913 £2 Kangaroo
SRC 40a - 26 Oct 2001- Kangaroo and Map (Black Print)
SRC 41 - 4 Oct 2002 - 1955 Cobb & Co
SRC 41a - 04 Oct 2002 - 1955 Cobb & Co (Black Print)
SRC 42 - 2004 - 1954 3½d Centenary of the First WA Stamp
SRC 42a - 2004 - 1954 3½d Centenary of the First WA Stamp (Black Print)
SRC 43 - 2005 - 1955 3½d Rotary International
SRC 43a - 2005 - 1955 3½d Rotary International (Black Print)
SRC 44 - 2006 - 1930 Centenary of Sturt's Exploration
SRC 44a - 2006 - 1930 Centenary of Sturt's Exploration (Black Print)
SRC 45 - 15 Jul 2007 - 1957 First AAT Stamp
SRC 45a - 15 Jul 2007 - 1957 First AAT Stamp (Black Print)
SRC 46 - 14 Mar 2008 - 1948 & 1952 Scouts
SRC 46a - 14 Mar 2008 - 1948 & 1952 Scouts (Black Print)
SRC 47 - 23 Jul 2009 - 1954 Centenary of Railways in Australia
SRC 47a - 23 Jul 2009 - 1954 Centenary of Railways in Australia (Black Print)
SRC 48 - 12 Mar 2010 - 1960 Melbourne Cup
SRC 48a - 12 Mar 2010 - 1960 Melbourne Cup (Black Print)
SRC 49 - 31 Mar 2011 - 1961 Northern Territory Cattle Industry (5/-)
SRC 49a - 31 Mar 2011 - 1961 Northern Territory Cattle Industry (5/-) (Black Print)
SRC 50 - 16 Apr 2015 - 1965 50th Anniversary of ANZAC (8d)
SRC 50a - 16 Apr 2015 - 1965 50th Anniversary of ANZAC (8d) (Black Print)