Tom,
I haven't rebarreled any of my rifles, but I can tell you that I really like the two choices in cartridges that you want: 35 Whelen and .338-06. :grin:
These two, as you likely already know, are very similar in that they are based on 30-06 cartridges but one is opened to 35 caliber while the other is .338.
Both make great elk guns at modest ranges. I would like to use them on the big hogs in Texas.
I keep on waiting for one of the big gun manufacturers to chamber a stainless/synthetic rifle in the 35 whelen. Weatherby has their ultralight available in the .338-06, but that gun is just too light for my tastes.
Zachary