This option would be the more expensive route but you would get true 1:1 macro capability.
1.) Nikon D40 w/kit lens= $450
http://www.bhphotovideo.com/c/produc...al_Camera.html
+
2.)Sigma 50mm 1:1 Macro= $250, (No auto focus on the D40 but not a big need in precise macro work)
http://www.bhphotovideo.com/c/produc....html#features

This option is defiantly over your budget so it really depends on your needs in a camera. I also agree with blueapplepaste's post.

Hope this helps, --Josh