I have to admit that I like off-beat but capable cartridges so that 9.3X62 sounds appealing. Initial cash outlay might be a little higher when obtaining dies and components for hand loading but once acquired then you'd be there. Future care and feeding of the rifle would be pretty inexpensive unless one was going to shoot hundreds of rounds per year.
Once knew a fellow who built a custom bolt action rifle up on a late vintage Remington produced 1903 action and chambered it for .358 Norma Magnum. Was a lot like shooting a .338 Winchster Magnum. Looks good on paper and looked good over the chronograph. Would be about as off-beat to find as a 9.3X62.
I like the notion of the .35 Whelen and have an action earmarked for a custom rifle in either .35 Whelen or .358 Winchester, haven't made up my mind on that. Don't really have a needful hole to fill between the .30-06 and the .375 H&H Magnum in my sporter rifle collection but it'd be fun to play with.
Another round that Glockman10mm mentions is the grand ol' .300 H&H Magnum. I've long been intrigued by that one. Some of the older Lyman manuals show slightly higher max velocities for .300 H&H Magnum handloads than they do for .300 Winchester Magnum. Now most .300 H&H Magnum rifles of yore possessed 26-inch barrels which would certainly help velocities. I'd want a 26-inch barrel on a .30 Magnum anyway. I like longer barrels than are currently popular.
To my mind, the .30 caliber is the smallest bore diameter where "magnum" capabilities might be meaningful. The .30 Magnum rounds can do things with .308 component bullets in the 180-220 grain weights that yield some impressive down range punch.