I had a Gamo slugger many years ago, when 1000fps guns first started being advertised, it came with a 4x32 Gamo brand scope which has since served as a handle on many other guns and been generaly abused. Very clear optic and it's held up well.
Best thing for springers is to make sure the spring ends are square and the piston seal is good. Some tubes are made better with bushing. Strip out all the factory assembly grease and lube properly. Can't go too far wrong when you can shoot all day for ten bucks!