If you are looking for a very affordable 7-inch tablet from a reputable manufacturer then you should have a look at this HP 7-inch tablet that runs Android 4.1 Jelly Bean OS out of the box and has 8GB of internal storage. It is codenamed HP 7 1800.
This 7-inch HP tablet is powered by 1.6GHz Intel Atom Z2460 processor and has 1GB RAM. Other main features include a screen resolution of 1024 x 600, WiFi, Bluetooth, webcam, built-in microphone accelerometer etc.
The battery on HP 7-inch Android tablet lasts up to 5 hours and it weighs just under a pound. This HP 7-inch tablet is available at Amazon (see details).