I am a beginning shooter in F/TR. I would like to purchase 500 Lapua cases in .308 WIN. When I look on various websites that sell cases it looks like there are various types of Lapua cases. Are the ones which I should buy "LAPUA BRASS 308 WIN PALMA SR"? If not which ones? Is there a place I can purchase the cases so that all of the cases come from the same lot? Thanks!