Check here:
http://www.wideners.com/itemview.cfm?dir=278|281|1083|1136
They have several weights of semi wadcutters. I just bought the 255gr here for $105 per 1000 prepaid. They put them in a priority mail box and your mailman will love you when he has to take them to your door. 36lbs. They have several other deals in other calibers that are prepaid.
I have a couple of pounds of Blue Dot that I received with a package deal and I am going to see how 12 gr will do with the 255gr.
I will shoot these in a 25-5 8 3/8"
They also have 185gr and 200gr semi wadcutters. You have to pay for shipping on these.