Either a 7x57 with 140 grain NBT's, a .270 Win with 130 grain NBT's or a .30/06 with 150 grain NBT's.
No 460? are you feeling OK?
I would take my 338-06 with 210 grain monometal. Probably a TSX, but maybe a TTSX. Already have a TSX load worked up. TTSX's on the shelf, just have not tried them yet..
I have used 200gr Ballistic silvertips on deer and black bear. IMO it would tear up a leopard pretty good.