Of the choices above, the one that would provide the greatest long term retail value would definitely be the Zeiss. The conquest 3-9 is still manufactured in limited numbers in America and is a fantastic optic for around $300. If the rifle were mine, I would select that optic personally as I've found them to be great quality and if you need to move it down the river at a later date its the only one of the optics listed that would resale above fifty cents on the dollar.
Swarovski, Kahles, Zeiss, Leica, Schmidt & Bender, Wetzlar, Hensoldt
Will always hold more value (and are arguably better scopes) than the still well regarded:
Meopta, Leupold, Nikon, Burris, Redfield, Trijicon, Leatherwood, Hawke, Vortex, Nightforce, Weaver etc.
P.S. - Tang safety 257 Bob is one helluva gun. Congratulations on obtaining a truly fine gentleman's American deer rifle.
Swarovski, Kahles, Zeiss, Leica, Schmidt & Bender, Wetzlar, Hensoldt
Will always hold more value (and are arguably better scopes) than the still well regarded:
Meopta, Leupold, Nikon, Burris, Redfield, Trijicon, Leatherwood, Hawke, Vortex, Nightforce, Weaver etc.
P.S. - Tang safety 257 Bob is one helluva gun. Congratulations on obtaining a truly fine gentleman's American deer rifle.