you want a scope with adjustable objective. This allows you to set focus for the distance you are shooting. make sure you have a True air gun scope or a Tasco, Bushnell such scope. The reticle needs be etched on glass or the wire will become loose. The recoil is forward and soldered wired become damaged from air rifles.
Etched glass reticles will work on anything.
scope power is up to you.