Like others have stated that 4.5 - 14 range would be a nice range.
Using a Conquest 4.5-14 with mil-dot for one of my hunting/target setups, on my second one of these scopes.However the best bang for dollar right now is 3-9x40 Zeiss under $500.00 if 9X is sufficient for your needs.
Not sure if it is an issue for ya but some have constant eye relief throughout the magnification range(Zeiss) some are variable(Leupold).The VX3's and Conquest are going to be very close, can't go wrong with either one.I do favor the Zeiss glass for my eyes.
Make sure that the reticle is fine enough for your target purposes and you should be good to go.
If you are more budget oriented, you can also look at Sightron.