I’ve used Home Depot’s American Craftsman vinyl replacement windows in my home. They are very easy to install, energy rated and mechanically work very well. They have some sizes in stock and others are available on their quick ship plan. If you go to their store they usually have a chart available telling you exactly how to measure your current windows, what sizes are available and when and what the price is. The prices seem reasonable also (especially compared to some estimates we’ve had from window companies). Good luck.