If you are willing to pay a hefty price say
somewhere between 1100 to 1500 dollars
Swarovsky is a good choice as well as Zeiss,
but if you want something a little tamer on
the price Leupold would be my choice. I us
one on top of my 300 win mag in the VXIII,
not as high powered as you want but it does
a fine job out to 600 yards.