Hi All, I recently bought a Arkapovic slip-on for my '05 ZX636 and the cheapest in Australia was about AU$1100, so I did some google searches to see what was about in the world market.
I found a bike website in the US that does credit card orders and even with freight were much cheaper at AU $760 to my door. They are not an ebay store and use fax credit card authorisation forms for making payment.
Their site is;
http://www.HardRacing.com

Hard Racing Performance
224 Rolling Hill Rd. Ste. 7A
Mooresville, NC 28117
704-799-2192
They were very professional, fast with communication and fast with the delivery (About 5 business days).
I was very happy with their service, price and really wanted to pass on the site to anyone else who is feed up with high prices on locally sourced stuff.

(I am in no way affiliated with this company, I just had a good experience and thought you all should know).
Stay upright all.