Logitech G613 Wireless Mechanical Gaming Keyboard - $95.20 (MSRP $169 AUD / $129 USD)
Currently on sale for $119 at JB Hi-Fi and can be combined with their 20% promo for gaming accessories to get final price of $95.20. Shopping around it looks like EB games have it on sale for $108, PC Byte $139, PC Case Gear $155.
product review: https://www.youtube.com/watch?v=B5Mu1egaSDY
Still being sold for ~$100 USD in the U.S
This is a pretty good price for this particular keyboard, but compared to other mechanical keyboards, they aren't as good because what you expect from a mechanical keyboard is a mechanical feel (feedback) when you press down on the key. By mechanical, I'm comparing to the popularised Cherry MX keys which a lot of people compare to.
The Romer G keys are frequently reported to feel slightly sticky (I don't have one myself, just read a lot of reviews) which is similar to a brand-new $5 keyboard with silicon pads but at the same time, very unlike. You'll just have to get lucky and find a place where you can try it out.