The Cloak of the Two Hammers just dropped for me from Naruhel (a.k.a. The Red Maid) in the Garth Agarwen Fortress (she is the final boss). Also note that I have done the GA Fortress about 20 times on various characters and that cloak has only dropped for me once in all that time.
In answer to your second question about the items with mining time reductions, yes there are more. Any sort of crafted Prospector's Tools give you -Mining Time, depending on what type it is. For instance, the Superior Iron Prospector's Tools (min. level 13) gives -1s Mining Time, Superior Dwarf-Steel Prospector's Tools (min. level 35) gives -2s Mining Time, and Superior Ancient Steel Prospector's Tools (min. level 45) gives -3s Mining Time, to name a couple. Go onto the Lorebook and in the Advanced Search box search Prospector's Tools to see the list of all the different types, levels, and time-reduction of Prospector's Tools. I hope this helped!
(I'll try to get a screenshot on here, my minstrel has it)
Last edited by Legion-of-Pookas; Feb 15 2011 at 07:56 PM.