In the classifieds 2 new OEM Jamis 12mm axle derailleur hangers - Buy and Sell and Review Mountain Bikes and Accessories
$20 each or $35 for both. These were extras I bought for my 2011 Dakar 650 B2. Far as I can tell no aftermarket company is making this hanger so OEM is the only choice. Will most likely fit any Jamis with a 12 x 135 (142?) axle but you should know by looking at the pics.
Results 1 to 2 of 2