Dropped from Vodyanoi on the barge between 2000-0400 Vana time in Phanauet Channel. approximently a 12-15 hr respawn (Only because 2 barges travel at that timeframe).
Not easy to get at all, and not a common drop. I went 1/13 on these personally and wow, what a long month that was. That is when they were very expensive though, not sure why the price took a nosedive on my server but someone obviously dont know how much of a pain this guy is to camp.
I got it 1/1 while fishing newts. I've being killing it if it shows up when I'm fishing but I've killed like 10 and no drop so yeah it is indeed a rare drop. Easy solo on DRG too.
Aight, so I came to carpenter's landing to spawn a nm for "Black Hose" for my drk... Got on barge and here is a NM I have never seen XD So i just engage and destroy this thing. Got both drops, rdm pants and Nokizaru. ^^ Next day I came back and got drop again. THF ftw!!!!