I would just to newegg, laptops, set the filter for your acceptable screen sizes and price range and see if anything comes up. If yes, post here for opinions. If not, then you may need budget increase.
This really is a bad price point let alone bad time of the year to invest in a laptop.
After browsing through newegg, I came to this laptop based on a few reasons. http://www.newegg.com/Product/Product.aspx?Item=34-216-677
1: It says up to 5:36 hours of battery life, which can be raised much higher if you download the latest catalyst drivers, and underclock the cpu to the minimum catalyst allows you too.
2: It has a bigger hard drive space.
3: It's battery life even outside of underclocking is the best. You shouldn't have a problem underclocking your cpu since you're doing powerpoints, light internet surfing, and mild gaming. I really don't think gaming on a laptop like this though is ideal.