60x magnfication is WAY too much, for any spotting scope that won't be locked into a heavy mount (like a barrel of concrete). There's no way to see anything at 60x if the scope trembles in the slightest.
For your budget, take a real hard look at Kowa and the Nikon Fieldscope line. The scope Jerry mentions (no offense) has about 1/2" of eye relief, which is just not enough, and only has a 60mm objective, and the eyepiece is not detachable.
Check here for competitive Kowa pricing from a heck of a nice guy and great American, Jim Owens: http://www.jarheadtop.com/kowa.html
For interesting reviews on all spotting scopes, go here: http://www.betterviewdesired.com