I'm using the following brand (from Amazon)
http://www.amazon.com/gp/product/B00...164309-7326800
I guess it has good quality because I didn't have any problem lapping the 8k Norton...
one more thing....
I don't soak the Shapton in water before each use, I only spread some water over the stone before using it ( I do it because the instructions from Shapton say that)