RE: cheap spotting scopes
I honestly can't suggest anything as ones costing more then double have been poor for long range scouting IME, especially low light and trying to determine or judge headgear. Its been my experience with optics the higher the mag the moreapperent optic flaws become, so if your dead set on such a budget I would personally steer clear of the 60X's as they most likely will be as useful as "teets on a boar" at higher mag and that range.
Ie: MyWind River Sequoia at 45x was fine to a mile in good light, however in lower light it was a no go at that power and range. I have replaced it with a 20-60-80 Bushnell Elite, much better though in extremely low light it can get dim at 60x and I may need to back off to find a happy medium. If it weren't for a an exceptional deal on the Elite I would have saved more pennies and bought higher end still. I probably will some day but so far I am happy with this scope for its purpose: range and distance scouting/judging. I have a tripod and use it almost exclusively. I also have a window mount which I have usedwhile scouting waterfowl for years. Both of these scopes are more thenthose you mention or budgeted. Sorry probably of little help to you. May be put the money towards a better set of bins instead???
Good Luck