Look at Midway USA for their Redfield and the BSA lower lines. About $50 and better glass than the Centerpoints from walmart or NCStar.
IMHO, you don't need zoom on a rimfire - fixed power of about 4x (6x if you bought a bull barrel) will do most everything you want it to. With a 4X Simmons on my 10/22 I can chase golf balls at 100 yards without much problem.