Razer Blackwidow Ultimate 2013 Elite Keyboard for $139.95 at TopBuy
MWave, i-Tech and Computer Alliance also have discounted offers on this keyboard, but their shipping-included prices are all above $160. I did find another retailer selling it for less than this, Greenboxit.com.au for $149, but I can't vouch for their service as I've never used them before.
This keyboard's mechanical key-presses are a satisfaction unto themselves, it's backlit, has USB and headphone/mic pass-throughs giving ease-of-access to ports as well as a flexible macro and customisation system. Cnet.com.au gave it a 9/10 score in a review done during May of this year.
This deal expires on Wednesday 3rd of July.