I just bought one of these a few weeks back NOS for $160 the BK2005 which is it's older brother and replaced it is $307 I think. THey are $74 used on Ebay. This is the place I got from.
http://www.instock901.com/gw-instek-grg-450b-rf-signal-generator-ham-radio-test-equipment
http://www.instock901.com/gw-instek-grg-450b-rf-signal-generator-ham-radio-test-equipment