Astra coupes smallest engines are 1.6's, there quite rare, and pritty basic. Also the performance isnt the best on them. I would go for the 1.8, average of 35mpg, 125 horses, nippy, 0-60 in 8.5seconds. The 1.8 is a good car.
If you spend around 2k, you can get a good example of an se2, about 70k-80k miles, half leather, half suede, 17" alloys, good car Got big boots too!
Why are you after a 1.4 or 1.6? If you dont mind me asking?