Are you hoping to do the type of shooting with the airgun that you would be otherwise be doing with your .22? If so, what kind of shooting do you enjoy? The FWB 300s is a terrific gun, have had mine for 35 years, but it is heavy at 10+ pounds without scope. You would either have to shoot it from some kind of supported position, or learn how to handle the weight. I use mine for 10 meter shooting indoors primarily, but occasionally put on a scope and shoot it off a bench or bipod outdoors, and have even used it to eliminate sparrows from my bluebird boxes.
For general casual target shooting indoors or out, the HW50s is a good suggestion. The power is plenty for target shooting out to 50 yards, it is not overly heavy, and it is quiet enough not to be a problem indoors. Like all the HWs, it is a quality gun that will last multiple lifetimes.