I LIKE your cartridge selection! Haven't tried that Ruger, but Ruger tends to build a good rifle. My son and I have taken several bear. He always uses his .30-06, with a 165 grain Nosler Partition at 2750 fps, which is very similar to the .308 Win. I took mine in 2016 with a .30-06 and a 165 gr Nosler Ballistic Tip at 2900 fps, and it worked fine. One shot, one bear. Am convinced that a hunter of your experience, will do just fine. I like the idea of the Nosler Partition BTW. Have been using those for several decades, and they just work!
I'd use a .308 with good bullets in a heartbeat!
I'm using a 1.5-5x Leupold scope on my bear rifle these days. I've used it on a 320 yard bear and on a 10 - 15 foot distance bear... Worked great on both situations.
Please update us with photos of the rifle and of your next hunt!