Your argument is flawed. Max altitude for Anza Mk2 is 4000m, if you are firing from a mountain the altitude above sea level is added to that. For eg for Kargil the altitude is 2,676 m above sea level so if a Anza 2 is fired from that type of location it will now have a max engagement altitude of 4000+2676 = 6676m. Apache ceiling is 6,400m but from web searches it rarely exceeds 2889m with combat load, LCH ceiling is 6500m but max tested for high altitude operation has been 15800/4815.84m. In reality neither numbers matter because what is quoted is usually under ideal conditions and minimal loadouts/reduced ranges.
However the real flashpoint is that Pakistan has between 4000-5500 MANPAD missiles (actual number is unknown) in it's inventory and that is a huge number. According to wikipedia Anza-1 & 2 production is 2650 (1000+2650) and Anza-3 is in production since 2012-13. And then there are the Stinger, Chinese and other EU procurements.
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Anza Mk-II - A third generation MANPADS,
[25] believed to be based on the Chinese
QW-1 MANPADS.
[26] Uses a dual-band, cross-scan
infra-red homing seeker to counter
decoy flares.
[27] Also believed to use American missile technology.
[28] Approximately 1650 Anza Mk-II were produced between 1994-2012.
[29]
- Anza Mk-III - Believed to be based on the Chinese QW-2 MANPADS,[30] modifications made to meet Pakistan Army requirements include increased range up to 5 km, improved sensors and a new firing unit similar to the Russian 9K38 Igla MANPADS.[31][32]((non reliable sources)) All-aspect attack capability and improved ECCM capability.[10] It also has a vehicle-mounted launcher variant.
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