low and extra low mount should work, but ideally you want to set the scope where it is natural to look through, use something like a stack of washers or coins to balance the scope on the receiver so you can shoulder the rifle, when you open your eye you should be centered on the scope, if it is to high, or to low, adjust with washers and repeat the process, once you find the ideal height simply measure the stack of coins and find a set of rings that are as close to that height as you can get, mount the bases on the rifle, toss the vortex in the trash and get a decent scope to mount in your new rings and you're set for years of hunting and shooting