A-4 Skyhawk Part III -- Foreign and civilian users:
https://en.wikipedia.org/wiki/Douglas_A-4_Skyhawk
Israel was the largest buyer of A-4s. From 1967, they bought 217 A-4s of several types. The A-4H was the first type and was essentially an A-4E modified for Israeli Air Force use. The A-4N followed and was based on the A-4M. The Israelis modified their A-4s with an extended exhaust tail pipe in the hope that infrared-homing missiles would detonate slightly further from the aircraft. They also fitted specific electronics systems of local manufacture. The Israeli Air Force also obtained 46 ex-US Navy A-4s under emergency conditions during the 1973 war. Israel operated the A-4 until 2015 and is now the source of many civil-registered A-4s used by Top Aces. (See below)
Argentina was the first country to get A-4s. From 1966 to 1976 they bought 91 used A-4Bs and A-4Cs for the air force and navy; these were designated A-4P and A-4Q. After the Falklands War with the UK, the US embargoed spare parts for the A-4s. Much later, in the late 1990s, the Argentine Air Force bought 36 ex-Marine A-4M and OA-4M aircraft and modified them into A-4ARs and OA-4ARs; they served until 2016.
The Royal Australian Navy got 20 new A-4Gs and TA-4Gs from 1967 to 1971 and operated them from the Navy's aircraft carrier until the early 1980s.
New Zealand's air force bought 14 new A-4Ks and TA-4Ks in 1970 and operated them until 2001, when they were retired leaving the country without a tactical jet combat aircraft. In the 1980s, the RNZAF modified their A-4 force under Project Kahu, making the A-4Ks some of the most capable A-4s in the world. Earlier, they had obtained the former RAN A-4Gs and added a number of these to their A-4 force.
Kuwait got new-productions A-4KUs and TA-4KUs in the late 1970s; during the Gulf War of 1991 these aircraft saw combat before being replaced by F-18s.
Indonesia got former Israeli A-4s in the late 1970s and supplemented them years later with surplus U.S. aircraft; they retired their A-4s in 2003.
Malaysia's A-4 fleet was one of the most interesting due to the odd designation used; their former USN A-4Cs and A-4Ls were designated A-4PTM (Peculiar To Malaysia)
They got 40 A-4s and flew them until 1995.
Brazil was a standout as they wanted A-4s to operate from their aircraft carrier. They got 23 ex-Kuwaiti A-4KUs/TA-4KUs in 1998 and operated them at sea for years; the Brazilian A-4s were essentially used up by 2022.
Lastly, Singapore operated a fairly substantial number of former U.S. A-4B and A-4C aircraft for a number of years as the A-4S and the odd TA-4S; the latter aircraft had a separate cockpit behind the usual one (see photo). Singapore also ultimately upgraded some of their A-4Ss with modern non-afterburning F404 turbofans and called the result the A-4SU Super Skyhawk. The A-4SU served until 2005 and was used as an advanced trainer until 2012.
https://en.wikipedia.org/wiki/ST_Aer..._Super_Skyhawk
That leaves the civil-registered A-4s. The primary source for these was retired Israeli A-4s and the distinctive extended exhaust pipe makes an ex-Israeli A-4 easy to identify. The Canadian company Top Aces is the largest operator and uses their A-4Ns to provide aggressor (adversary) services in at least the U.S., Germany and Canada. Draken flies ex-New Zealand A-4Ks for similar purposes.
The 2,960 A-4s built by Douglas have certainly left their mark in war and peace and apparently will continue to do for years to come.