One thing about the 760 pumpers... For $10 and a little elbow grease they can turned into serious shooters. The rifled barrel off the Mk4-177 is a "drop-in" replacement, and with a little cleaning up on the crown you can have a worthy tack driver. The older models take a scope quite well, too.
Regarding 880s- one of our forum members offers LDCs for them that also stabilize the barrel. The 880 is probably the most accurate gun for the budget airgunner, and they offer enough power for pesting, smallest-game hunting (rabbits and squirrel, mourning dovs, etc), and general plinking at range.