well, give malo mart 1000 rupees, they repair the bridge, then talk to the goron outside of it (funny lookin one) and do the little mission carrying the hot spring water to the goron on the bridge, then give malo mart 200 rupees, then they buy out the store in hyrule town, make sure you get the 600 rupee wallet from the bug catcher girl (giver her a pair of the same bug) and then buy it for 598 rupees
its not that great. basically it slowly drains your rupees while you wear it but if you get hit you wont lose health. but once you run out of rupees the armor will make you start moving as if you were wearing iron boots.