Just dropped for me the other day. Can't remember if it was from Act 2 cache or from Act 4 cache (which drops all act items). I've done just over 100 bounties (got the achievement yesterday). I've also gotten Royal Ring of Grandeur, but those are the only two cache items that have dropped for me. Not too bad though for ~20 caches.
I have 1660 bounties done without the gloves coming even once. At least 500 of these were on Torment 1 (mostly before I started hardcore farming for them) but the large large majority were done in Act2 Normal. Currently counted somewhere near 20 each of the shield and cloak, and 3 boots.
http://us.battle.net/d3/en/profile/barrybondz-1111/hero/17437659
http://us.battle.net/d3/en/profile/barrybondz-1111/hero/17437659
http://us.battle.net/d3/en/profile/barrybondz-1111/hero/17437659
http://us.battle.net/d3/en/profile/barrybondz-1111/hero/17437659