I do not think this information available to the public. Anyway, go with the latest available.
Make sure you get it with Autonomous image on it (k9w7 - refer below post for more detail). Otherwise you required a WLC - Wireless LAN Controller to manage that AP. Without Cisco maintenance contract you cannot download autonomous image from cisco.com
https://mrncciew.com/2012/10/20/lightweight-to-autonomous-conversion
HTH
Rasika
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