There's no reason whatsoever to buy a Nikon or a Leupold. At that point, you're just paying for the name. I have a Tasco 3x9x50mm on my Remington 597, and it is more than adequate. I'm pretty sure I paid something like $57 for it at Walmart. It's just as dependable as my Leupold Vx-2 that I picked up for over $300. There's no noticeable difference. You'd have no problem hitting those targets even past 150 yards.
Are you kidding? Good glass costs money. Period.