Mamma bears will have cubs on the periphery to where the boars are feeding, on smaller tributaries or in wider spots. Boars get premium fishing spots. With that said the risk is a hungry young bear who knows a gunshot means gut pile. This is true closer to town more so than remote, your dealing with peninsula browns they are big lumbering mostly predictable critters. I'd take the gun you have the most confidence in making the best shot. Be a different conversation if we're arguing 243 or 300 win mag. All your rifles are withing a few hundred fps with equal weight bullets with similar constructed bullets, splitting hairs really.
In 15' and 16' we had dry winters with dry windy summers, many of the fish were deep and consolidated to specific rivers. From kodiak to Bristol Bay, those were some of the most aggressive bears I'd ever seen. This year has massive fish numbers, spread nicely into the tributaries. Berry production in the tundra has been awesome, bears are going to be fat this fall. Bears always pose some risk, but I'd doubt this year its going to be much above status quo.