ORIGINAL: Briman
I would forget about the autoloader for deer hunting. In that price range you will not find an autoloader that is both powerful and accurate enough for deer hunting.
Actually a Glock 20 can be had for that price and is plenty accurate. Top Glock has brand new Glock 20's for $484
http://www.topglock.com/catalog/pistols.htm He also sales 6" hunting barrels for the Glock 20. Double Tab Ammo sales 10 mm hunting ammo as does Corbon
http://www.corbon.com that has plenty of power. Top Glock also sells mounts and optics for the Glock 20.