I had a Ruger 77 in .250 Savage and still have a Savage 99. The Ruger seemed a little clunky for the cartridge and the chamber was oversized so I wound up selling it. To my mind, the .250 Savage belongs in the smaller rifles, Featherweights, etc.
It's a perking little cartridge and well worth having, but were I rebarrelling a .243, I'd sure look into building a .25 Souper. With your ammo supply problems, a wildcat on the .308 family of cartridges would make better sense.
You can, and I have, form .250 Savage cases from .308, but it's a chore and not really worth doing.