Well, you have a lot of time to think about it. You have a lot of resources you can call upon; Doc White will be happy to tell you about the big (huge) muzzleloading bears he has taken over the years, as well as his time living in Alaska.
Brown bear is not considered dangerous game in a class with polar bear, grizzly, or cape buffalo. You can plan on multiple shots being put into your animal, or I believe you should. The first video I put out has Shockey talking a nice brown bear-- Loggy, was that three shots, or four? All were well placed, lethal shots-- according to the man that shot the video, and the guide I talked to that was there as well.
If the question is one of the Savage being enough gun, there is little doubt-- if you believe the .450 Marlin is adequate, the 10ML-II can be loaded hotter than that with no troubles.
As far as loads go, there is plenty of time for that as well. I've not experimented (punished) myself with anything heavier than a 375 gr. bullet.
I can tell you that 72 grains of 2015 pushing a 350 gr Barnes X is a sub-25,000 PSI load, good for about 2100 fps. Not only a 3/4 MOA load, it is also a 220 yard load w. an 8" kill. Over 1 ton of energy @ 200 yards strike distance.
That compares well with a .375 H & H pushing a 350 grain bullet. :shock: