I would vote for the 35 Whelen Might as well take advantage of the model 98's long action length. The 338-06 is also a viable choice. In practical terms, they are both pretty similar. I like the Whelen more for nostalgia, and a soft spot for 35 caliber.
I have a 1909 Argentine Mauser, made by DWM that I bought when I was 16. I had the barell cut down to 22 inches, had it re-bored / chambered to .35 Whelen, bolt handle lowered, drilled and tapped, mounted a Lyman peep sight, and re-contoured / refinished the wood. Still have that rifle, and would feel confident hunting about anything that walks with it.