Lotsa guns out there,,,, unless you just have your heart set on another GAMO I'd consider some of the others. How about an RWS 34 Panther ?? I have one in .22 and I have to tell you, it's one heck of a small game rifle..... Deadly accurate, nice shooting, well balanced, well made and excellent power. It quickly became one of my favorite small game springers. The .177 Panther is a good option also for small game.
The Panther is just one gun that comes to mind.... Like Neil said,,,, you really need to state your spending limit as well as some other criteria in order to receive good recommendations. Side cocker ?? Under lever ?? Light ? Heavy ? etc.......
There's also a Mike Mellick B-26,,, you can never go wrong with one of them.....
I'm sure others will chime in with their suggestions......
Jeff