Meopta MeoSport R
Meopta Optika6
Trijicon Accupoint 2.5-10x56
Anyhese all will get you to 45 minutes after sunset in average conditions or longer in good. You have to spend a lot more to do any better. You can come in under budget if you shop a little. I'd mount in DNZ one-piece unless you use the rings that come with the MeoSport R. They're good, but they're tall.
Can you buy those new for $600?
