If all you want is a 1500 yrd shot, why get something that's going to kick that hard? My advice is build up a .308 or .22-250. You're going to save a ton of money on brass, and it's not going to kick you nearly as bad as what the .338 or the laupa will, and won't cost you an arm and a leg for brass. From what you listed though, if you aren't open to suggestion, I'd go with the .338, the .300 win mag isn't going to cut it at that range, and the laupa costs too much.

Screw the 10 ring, keep them in the zero!!!