Here's an 8x2" trans (at least looks pretty trans to me) for $52 + shipping
True Hard Arkansas Whetstone for Sharpening Knives NIB! - eBay (item 110465068371 end time Jan-01-10 08:26:17 PST)
It looks quite thin though.
Or this place has 6x2 for $45+ship
http://www.knifecenter.com/kc_new/st...il.html?s=AC66
Also that site pyment linked has a trip set of 6x2" for $37. It has hard black, soft and "medium" which I suspect is a hard white.