Or check this one- a Canon 20Da - which was a limited run model made by Caon especially for astrophotgraphy with live view focusing on the back LCD and a special filter over the chip with good Ha response but also useable during daylight.
I have seen lots of incredible images from those using this camera. It has other subtle modifications that make it ideal for astro work.
US$1100
http://www.astromart.com/classifieds...fied_id=584222
Greg.