Justsaws
Addicted to ArboristSite
http://www.arboristsite.com/pp-classifieds/showproduct.php?product=1962&cat=6
Have a look at this. Still probably on the small side but I'm sure it would pay for itself at least. There's an 066 for $400, that's what you really want. Honestly, I don't know anything at all about milling, but I'd look for a big older low revving torquey saw for cheap on craigslist or at a yard sale, etc...(Again, I'm sure this has been said before :monkey: )
The first saw on my mill was an 1100CD it was replaced with a 480CD. A perfect example of running and then walking.
If you are planning on milling a lot try and get a saw that still has parts available from a local dealer.