I definitely don't want a heavy barrel rifle. Plus a 243 you're talking 10 to 15 grains more powder. And I have an irrational hatred of the 243 Winchester.
interesting cartridge....the 6x45
mild & modest powder charge
A good SS barrel from CBI or others would be $3-350
8 twist & 20" sounds great
Screw it on a Savage action and go have fun